https://tests.bitcoin.it/w/api.php?action=feedcontributions&user=Prcarter&feedformat=atomBitcoin Wiki - User contributions [en]2024-03-28T09:36:40ZUser contributionsMediaWiki 1.30.0https://tests.bitcoin.it/w/index.php?title=Help_talk:Introduction&diff=16318Help talk:Introduction2011-09-08T06:44:50Z<p>Prcarter: </p>
<hr />
<div>I would like to create this page, describing bitcoin in an easy manner.<br />
---<br />
<br />
"These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce,"<br />
<br />
this seems to me the cost-theory of value, which is a fallacy. Digging holes in the ground requires spending of resources too.<br />
<br />
--<br />
<br />
Good page, but I was expecting a more concise introduction. Perhaps give it a more punchy, concise start?<br />
<br />
--[[User:Mcnalu|Mcnalu]] 14:43, 15 May 2011 (GMT)<br />
<br />
The idea for the "resources" talk was that people who spend CPU time and electricity to mine bitcoins will not want to simply give it away for free. The people who buy it from them later in exchange for something valuable also won't want to give it away cheaper, and so on. I think this kind of talk makes sense if you wish to promote Bitcoin because if you talk to people about it, basing its "worth" on how many people are already using it (how "useful" it is), you are conceding to Bitcoin's being subject to network effects, which, if it is, it is not going to survive. I hate to see great ideas like this going down because of stupid chicken-and-egg problems.<br />
<br />
I suppose it's easy to present this all as useless electricity wasting, but at least it's based on something real. You spend this much electricity/CPU time, you get this many bitcoins. The alternative is the "good" old papers+guns system. What is that based on?<br />
<br />
I haven't been following the arguments about the "gold standard" and whether it's "good" or "bad", and things like that. Haven't been in the forum much lately. Perhaps we could argue indefinitely about this. IMO, it's better for Bitcoin if the introduction talks about tangible things (maybe electricity isn't "tangible" but at least it's not dependent on people).<br />
<br />
I'm going to change the phrase to talk about both the "usefulness" and the resources.<br />
<br />
--[[User:Prcarter|Prcarter]] 06:29, 8 September 2011 (GMT)<br />
<br />
This introduction shows Bitcoin's place and how it relates to the traditional banking system. It's to make people conscious of what is really going on and of the level of trust they are already placing on banks and those printed pieces of paper we base our survival on. I would hate a "buy bitcoins, they are cool"-type "promo".<br />
<br />
--[[User:Prcarter|Prcarter]] 06:40, 8 September 2011 (GMT)<br />
<br />
Yes, "maintaining account balances" tones it down a little.<br />
<br />
--[[User:Prcarter|Prcarter]] 06:44, 8 September 2011 (GMT)<br />
<br />
== it.bitcoin.it ==<br />
<br />
I've started filling-in a few sections of the Italian version it.bitcoin.it. If you don't mind, I am using this page as the basis. So, I'm translating it and tightening it up at the same time. Would it be OK? I've also added a summary, using the bitcoin entry in wikipedia.<br />
<br />
ciao<br />
<br />
[[User:Gianco|Gianco]] 19:50, 16 June 2011 (GMT)<br />
<br />
==Banking and Money, in general==<br />
<br />
I am not sure about all the users of this site who are interested in and trying to understand BitCoin (as I am), but personally, I found myself, even quite recently, without an understanding about how banking and money works at all. The Khan Academy video series on banking and money was very helpful, I thought perhaps you might want to include a link in the Introduction and Basic Concepts. http://www.khanacademy.org/#banking-and-money<br />
I think the more regular people can understand these basic things, the more they will be interested and engaged.<br />
<br />
Thanks and great work so far it seems<br />
<br />
[[User:Cruiser moves|Cruiser moves]] 12:44, 23 June 2011 (GMT)<br />
<br />
== Confusion : how the Money is valued ==<br />
<br />
The introduction is not upfront enough as to how Bitcoins get their value and why people are prepared to except them as money.ie We need on overview of the introduction to explain this without the explainations as to how they are created and cannot be duplicated. I gather what happens is that as long as there are enough people with things to sell and willing buyers then the money then gets its value due to its expanding usage.That is someone who has sold something can then turn around and buy something else with a bitcoin. Is that right?<br />
And since the coins themselves are made scare by the design of their creation(time and energy) and their intrinsic unforgability (due to the mathematics) they then can be traded with confidence.Yes?</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=16317Help:Introduction2011-09-08T06:43:50Z<p>Prcarter: </p>
<hr />
<div>The purpose of this page is to provide a general overview of the Bitcoin system and economy.<br />
<br />
==Basic Concepts==<br />
<br />
===Currency===<br />
<br />
Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
===Banks===<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to maintain account balances. These bitcoins are valuable because they are useful, they are limited in supply and because producing them requires spending real resources such as electricity and CPU time.<br />
<br />
==Bitcoin Basics==<br />
<br />
===Creation of coins===<br />
The creation of coins must be limited for the currency to have any value. <br />
<br />
New coins are slowly "mined" into existence by following a mutually agreed-upon set of rules. A user "mining" bitcoins is running a program that searches tirelessly for a solution to a very difficult math problem whose difficulty is precisely known. The difficulty is automatically adjusted regularly so that the number of solutions found globally, by everyone, is constant: an average of 6 per hour. When a solution is found, the user may tell everyone of the existence of this new found solution, along with other information, packaged together in what is called a "block". <br />
<br />
Blocks contain 50 bitcoins at present. This amount is an incentive for people to perform the computation work required for block generation. Roughly every 4 years, the number of bitcoins that can be "mined" in a block reduces by 50%. Any blocks that are created by a malicious user that do not follow this rule (or any other rules) will be rejected by everyone else. The result is that no more than 21 million bitcoins will ever exist. <br />
<br />
Because the "mining" incentive to put fourth the computational power to create blocks will eventually diminish, miners will some day pay for their hardware and electricity costs by collecting [[Transaction_fee|transaction fees]]. The sender of money may voluntarily pay a small transaction fee which will be kept by whoever finds the next block. Paying this fee will encourage the miner to include the transaction in a block more quickly.<br />
<br />
===Transferring a coin===<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
Suppose Alice wants to send a bitcoin to Bob.<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer to a message: a 'transaction' message.<br />
* Alice signs the transaction with her secret private key.<br />
* Alice broadcasts the transaction out over the bitcoin network for all to see.<br />
<br />
(Only the first step is actually completed by a human. The rest is done by the bitcoin client software.)<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her control.<br />
<br />
Later on, when Bob wishes to transfer the same bitcoin to Charley, he will do the same thing:<br />
* Charlie sends Bob his public key.<br />
* Bob adds Charlie's public key along with the amount he wants to transfer to a message: a 'transaction' message.<br />
* Bob signs the transaction with his private key.<br />
* Bob broadcasts the transaction out over the bitcoin network for all to see. <br />
<br />
Only Bob can do this because only Bob has the private key that corresponds to the public key Alice included in the previous transaction. <br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
===Preventing double-spending===<br />
The process described above does not prevent Alice from using a coin in more than one transaction. The following process does. This is the primary innovation behind Bitcoin.<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and it is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and is permanently recorded, preventing Alice from creating a second transaction with the same coin. In order for Alice to thwart this system and double-spend her coins, she would need to muster more computing power than all other bitcoin users combined.<br />
<br />
===Anonymity===<br />
There are no bitcoin "accounts" to set up, no e-mail addresses and no user-names and passwords to give, just for owning bitcoins. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. Moreover, those keys do not have to be registered anywhere in advance, as they are only actually used if and when there is a transaction involving them. Transacting parties do not need to know each other's identity in the same way that a store owner does not know Bob's name is Bob when Bob goes and buys groceries with cash.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, which makes it very difficult to know which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. The Bitcoin software encourages this behavior by default. Continuing the example from above, when Charlie receives the bitcoin from Bob, Charlie will not be able to identify who owned the coin before Bob (not without asking Bob).<br />
<br />
You have completed reading our Bitcoin introduction!<br />
<br />
==Where to see and explore==<br />
You can directly explore the system in action by visiting the [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour which on average will be 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K).<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros. This what made making it so difficult; a hash that begins with many zeros is much more difficult to find than a hash with few or no zeros. The computer that generated this block had to try many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed. Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]<br />
<br />
[[zh-cn:简介]]<br />
<br />
[[de:Einführung]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help_talk:Introduction&diff=16316Help talk:Introduction2011-09-08T06:40:15Z<p>Prcarter: </p>
<hr />
<div>I would like to create this page, describing bitcoin in an easy manner.<br />
---<br />
<br />
"These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce,"<br />
<br />
this seems to me the cost-theory of value, which is a fallacy. Digging holes in the ground requires spending of resources too.<br />
<br />
--<br />
<br />
Good page, but I was expecting a more concise introduction. Perhaps give it a more punchy, concise start?<br />
<br />
--[[User:Mcnalu|Mcnalu]] 14:43, 15 May 2011 (GMT)<br />
<br />
The idea for the "resources" talk was that people who spend CPU time and electricity to mine bitcoins will not want to simply give it away for free. The people who buy it from them later in exchange for something valuable also won't want to give it away cheaper, and so on. I think this kind of talk makes sense if you wish to promote Bitcoin because if you talk to people about it, basing its "worth" on how many people are already using it (how "useful" it is), you are conceding to Bitcoin's being subject to network effects, which, if it is, it is not going to survive. I hate to see great ideas like this going down because of stupid chicken-and-egg problems.<br />
<br />
I suppose it's easy to present this all as useless electricity wasting, but at least it's based on something real. You spend this much electricity/CPU time, you get this many bitcoins. The alternative is the "good" old papers+guns system. What is that based on?<br />
<br />
I haven't been following the arguments about the "gold standard" and whether it's "good" or "bad", and things like that. Haven't been in the forum much lately. Perhaps we could argue indefinitely about this. IMO, it's better for Bitcoin if the introduction talks about tangible things (maybe electricity isn't "tangible" but at least it's not dependent on people).<br />
<br />
I'm going to change the phrase to talk about both the "usefulness" and the resources.<br />
<br />
--[[User:Prcarter|Prcarter]] 06:29, 8 September 2011 (GMT)<br />
<br />
This introduction shows Bitcoin's place and how it relates to the traditional banking system. It's to make people conscious of what is really going on and of the level of trust they are already placing on banks and those printed pieces of paper we base our survival on. I would hate a "buy bitcoins, they are cool"-type "promo".<br />
<br />
--[[User:Prcarter|Prcarter]] 06:40, 8 September 2011 (GMT)<br />
<br />
== it.bitcoin.it ==<br />
<br />
I've started filling-in a few sections of the Italian version it.bitcoin.it. If you don't mind, I am using this page as the basis. So, I'm translating it and tightening it up at the same time. Would it be OK? I've also added a summary, using the bitcoin entry in wikipedia.<br />
<br />
ciao<br />
<br />
[[User:Gianco|Gianco]] 19:50, 16 June 2011 (GMT)<br />
<br />
==Banking and Money, in general==<br />
<br />
I am not sure about all the users of this site who are interested in and trying to understand BitCoin (as I am), but personally, I found myself, even quite recently, without an understanding about how banking and money works at all. The Khan Academy video series on banking and money was very helpful, I thought perhaps you might want to include a link in the Introduction and Basic Concepts. http://www.khanacademy.org/#banking-and-money<br />
I think the more regular people can understand these basic things, the more they will be interested and engaged.<br />
<br />
Thanks and great work so far it seems<br />
<br />
[[User:Cruiser moves|Cruiser moves]] 12:44, 23 June 2011 (GMT)<br />
<br />
== Confusion : how the Money is valued ==<br />
<br />
The introduction is not upfront enough as to how Bitcoins get their value and why people are prepared to except them as money.ie We need on overview of the introduction to explain this without the explainations as to how they are created and cannot be duplicated. I gather what happens is that as long as there are enough people with things to sell and willing buyers then the money then gets its value due to its expanding usage.That is someone who has sold something can then turn around and buy something else with a bitcoin. Is that right?<br />
And since the coins themselves are made scare by the design of their creation(time and energy) and their intrinsic unforgability (due to the mathematics) they then can be traded with confidence.Yes?</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help_talk:Introduction&diff=16315Help talk:Introduction2011-09-08T06:29:12Z<p>Prcarter: </p>
<hr />
<div>I would like to create this page, describing bitcoin in an easy manner.<br />
---<br />
<br />
"These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce,"<br />
<br />
this seems to me the cost-theory of value, which is a fallacy. Digging holes in the ground requires spending of resources too.<br />
<br />
--<br />
<br />
Good page, but I was expecting a more concise introduction. Perhaps give it a more punchy, concise start?<br />
<br />
--[[User:Mcnalu|Mcnalu]] 14:43, 15 May 2011 (GMT)<br />
<br />
The idea for the "resources" talk was that people who spend CPU time and electricity to mine bitcoins will not want to simply give it away for free. The people who buy it from them later in exchange for something valuable also won't want to give it away cheaper, and so on. I think this kind of talk makes sense if you wish to promote Bitcoin because if you talk to people about it, basing its "worth" on how many people are already using it (how "useful" it is), you are conceding to Bitcoin's being subject to network effects, which, if it is, it is not going to survive. I hate to see great ideas like this going down because of stupid chicken-and-egg problems.<br />
<br />
I suppose it's easy to present this all as useless electricity wasting, but at least it's based on something real. You spend this much electricity/CPU time, you get this many bitcoins. The alternative is the "good" old papers+guns system. What is that based on?<br />
<br />
I haven't been following the arguments about the "gold standard" and whether it's "good" or "bad", and things like that. Haven't been in the forum much lately. Perhaps we could argue indefinitely about this. IMO, it's better for Bitcoin if the introduction talks about tangible things.<br />
<br />
I'm going to change the phrase to talk about both the "usefulness" and the resources.<br />
<br />
--[[User:Prcarter|Prcarter]] 06:29, 8 September 2011 (GMT)<br />
<br />
== it.bitcoin.it ==<br />
<br />
I've started filling-in a few sections of the Italian version it.bitcoin.it. If you don't mind, I am using this page as the basis. So, I'm translating it and tightening it up at the same time. Would it be OK? I've also added a summary, using the bitcoin entry in wikipedia.<br />
<br />
ciao<br />
<br />
[[User:Gianco|Gianco]] 19:50, 16 June 2011 (GMT)<br />
<br />
==Banking and Money, in general==<br />
<br />
I am not sure about all the users of this site who are interested in and trying to understand BitCoin (as I am), but personally, I found myself, even quite recently, without an understanding about how banking and money works at all. The Khan Academy video series on banking and money was very helpful, I thought perhaps you might want to include a link in the Introduction and Basic Concepts. http://www.khanacademy.org/#banking-and-money<br />
I think the more regular people can understand these basic things, the more they will be interested and engaged.<br />
<br />
Thanks and great work so far it seems<br />
<br />
[[User:Cruiser moves|Cruiser moves]] 12:44, 23 June 2011 (GMT)<br />
<br />
== Confusion : how the Money is valued ==<br />
<br />
The introduction is not upfront enough as to how Bitcoins get their value and why people are prepared to except them as money.ie We need on overview of the introduction to explain this without the explainations as to how they are created and cannot be duplicated. I gather what happens is that as long as there are enough people with things to sell and willing buyers then the money then gets its value due to its expanding usage.That is someone who has sold something can then turn around and buy something else with a bitcoin. Is that right?<br />
And since the coins themselves are made scare by the design of their creation(time and energy) and their intrinsic unforgability (due to the mathematics) they then can be traded with confidence.Yes?</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=15328Help:Introduction2011-08-20T18:48:03Z<p>Prcarter: /* Anonymity */</p>
<hr />
<div>The purpose of this page is to provide a general overview of the Bitcoin system and economy.<br />
<br />
==Basic Concepts==<br />
<br />
===Currency===<br />
<br />
Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
===Banks===<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to maintain account balances. These bitcoins are valuable because they are useful and because they are limited in supply.<br />
<br />
==Bitcoin Basics==<br />
<br />
===Creation of coins===<br />
The creation of coins must be limited for the currency to have any value. <br />
<br />
New coins are slowly "mined" into existence by following a mutually agreed-upon set of rules. A user "mining" bitcoins is running a program that searches tirelessly for a solution to a very difficult math problem whose difficulty is precisely known. The difficulty is automatically adjusted regularly so that the number of solutions found globally, by everyone, is constant: an average of 6 per hour. When a solution is found, the user may tell everyone of the existence of this new found solution, along with other information, packaged together in what is called a "block". <br />
<br />
Blocks contain 50 bitcoins at present. This amount is an incentive for people to perform the computation work required for block generation. Roughly every 4 years, the number of bitcoins that can be "mined" in a block reduces by 50%. Any blocks that are created by a malicious user that do not follow this rule (or any other rules) will be rejected by everyone else. The result is that no more than 21 million bitcoins will ever exist. <br />
<br />
Because the "mining" incentive to put fourth the computational power to create blocks will eventually diminish, miners will some day pay for their hardware and electricity costs by collecting [[Transaction_fee|transaction fees]]. The sender of money may voluntarily pay a small transaction fee which will be kept by whoever finds the next block. Paying this fee will encourage the miner to include the transaction in a block more quickly.<br />
<br />
===Transferring a coin===<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
Suppose Alice wants to send a bitcoin to Bob.<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer to a message: a 'transaction' message.<br />
* Alice signs the transaction with her secret private key.<br />
* Alice broadcasts the transaction out over the bitcoin network for all to see.<br />
<br />
(Only the first step is actually completed by a human. The rest is done by the bitcoin client software.)<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her control.<br />
<br />
Later on, when Bob wishes to transfer the same bitcoin to Charley, he will do the same thing:<br />
* Charlie sends Bob his public key.<br />
* Bob adds Charlie's public key along with the amount he wants to transfer to a message: a 'transaction' message.<br />
* Bob signs the transaction with his private key.<br />
* Bob broadcasts the transaction out over the bitcoin network for all to see. <br />
<br />
Only Bob can do this because only Bob has the private key that corresponds to the public key Alice included in the previous transaction. <br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
===Preventing double-spending===<br />
The process described above does not prevent Alice from using a coin in more than one transaction. The following process does. This is the primary innovation behind Bitcoin.<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and it is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and is permanently recorded, preventing Alice from creating a second transaction with the same coin. In order for Alice to thwart this system and double-spend her coins, she would need to muster more computing power than all other bitcoin users combined.<br />
<br />
===Anonymity===<br />
There are no bitcoin "accounts" to set up, no e-mail addresses and no user-names and passwords to give, just for owning bitcoins. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. Moreover, those keys do not have to be registered anywhere in advance, as they are only actually used if and when there is a transaction involving them. Transacting parties do not need to know each other's identity in the same way that a store owner does not know Bob's name is Bob when Bob goes and buys groceries with cash.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, which makes it very difficult to know which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. The Bitcoin software encourages this behavior by default. Continuing the example from above, when Charlie receives the bitcoin from Bob, Charlie will not be able to identify who owned the coin before Bob (not without asking Bob).<br />
<br />
You have completed reading our Bitcoin introduction!<br />
<br />
==Where to see and explore==<br />
You can directly explore the system in action by visiting the [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour which on average will be 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K).<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros. This what made making it so difficult; a hash that begins with many zeros is much more difficult to find than a hash with few or no zeros. The computer that generated this block had to try many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed. Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]<br />
<br />
[[zh-cn:简介]]<br />
<br />
[[de:Einführung]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=15327Help:Introduction2011-08-20T18:45:53Z<p>Prcarter: some people wanted to know where they would get their user-names and passwords...</p>
<hr />
<div>The purpose of this page is to provide a general overview of the Bitcoin system and economy.<br />
<br />
==Basic Concepts==<br />
<br />
===Currency===<br />
<br />
Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
===Banks===<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to maintain account balances. These bitcoins are valuable because they are useful and because they are limited in supply.<br />
<br />
==Bitcoin Basics==<br />
<br />
===Creation of coins===<br />
The creation of coins must be limited for the currency to have any value. <br />
<br />
New coins are slowly "mined" into existence by following a mutually agreed-upon set of rules. A user "mining" bitcoins is running a program that searches tirelessly for a solution to a very difficult math problem whose difficulty is precisely known. The difficulty is automatically adjusted regularly so that the number of solutions found globally, by everyone, is constant: an average of 6 per hour. When a solution is found, the user may tell everyone of the existence of this new found solution, along with other information, packaged together in what is called a "block". <br />
<br />
Blocks contain 50 bitcoins at present. This amount is an incentive for people to perform the computation work required for block generation. Roughly every 4 years, the number of bitcoins that can be "mined" in a block reduces by 50%. Any blocks that are created by a malicious user that do not follow this rule (or any other rules) will be rejected by everyone else. The result is that no more than 21 million bitcoins will ever exist. <br />
<br />
Because the "mining" incentive to put fourth the computational power to create blocks will eventually diminish, miners will some day pay for their hardware and electricity costs by collecting [[Transaction_fee|transaction fees]]. The sender of money may voluntarily pay a small transaction fee which will be kept by whoever finds the next block. Paying this fee will encourage the miner to include the transaction in a block more quickly.<br />
<br />
===Transferring a coin===<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
Suppose Alice wants to send a bitcoin to Bob.<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer to a message: a 'transaction' message.<br />
* Alice signs the transaction with her secret private key.<br />
* Alice broadcasts the transaction out over the bitcoin network for all to see.<br />
<br />
(Only the first step is actually completed by a human. The rest is done by the bitcoin client software.)<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her control.<br />
<br />
Later on, when Bob wishes to transfer the same bitcoin to Charley, he will do the same thing:<br />
* Charlie sends Bob his public key.<br />
* Bob adds Charlie's public key along with the amount he wants to transfer to a message: a 'transaction' message.<br />
* Bob signs the transaction with his private key.<br />
* Bob broadcasts the transaction out over the bitcoin network for all to see. <br />
<br />
Only Bob can do this because only Bob has the private key that corresponds to the public key Alice included in the previous transaction. <br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
===Preventing double-spending===<br />
The process described above does not prevent Alice from using a coin in more than one transaction. The following process does. This is the primary innovation behind Bitcoin.<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and it is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and is permanently recorded, preventing Alice from creating a second transaction with the same coin. In order for Alice to thwart this system and double-spend her coins, she would need to muster more computing power than all other bitcoin users combined.<br />
<br />
===Anonymity===<br />
There are no bitcoin "accounts" to set up, no e-mail addresses and no user-names and passwords to give. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. Moreover, those keys do not have to be registered anywhere in advance, as they are only actually used if and when there is a transaction involving them. Transacting parties do not need to know each other's identity in the same way that a store owner does not know Bob's name is Bob when Bob goes and buys groceries with cash.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, which makes it very difficult to know which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. The Bitcoin software encourages this behavior by default. Continuing the example from above, when Charlie receives the bitcoin from Bob, Charlie will not be able to identify who owned the coin before Bob (not without asking Bob).<br />
<br />
You have completed reading our Bitcoin introduction!<br />
<br />
==Where to see and explore==<br />
You can directly explore the system in action by visiting the [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour which on average will be 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K).<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros. This what made making it so difficult; a hash that begins with many zeros is much more difficult to find than a hash with few or no zeros. The computer that generated this block had to try many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed. Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]<br />
<br />
[[zh-cn:简介]]<br />
<br />
[[de:Einführung]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=15326Help:Introduction2011-08-20T18:40:09Z<p>Prcarter: </p>
<hr />
<div>The purpose of this page is to provide a general overview of the Bitcoin system and economy.<br />
<br />
==Basic Concepts==<br />
<br />
===Currency===<br />
<br />
Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
===Banks===<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to maintain account balances. These bitcoins are valuable because they are useful and because they are limited in supply.<br />
<br />
==Bitcoin Basics==<br />
<br />
===Creation of coins===<br />
The creation of coins must be limited for the currency to have any value. <br />
<br />
New coins are slowly "mined" into existence by following a mutually agreed-upon set of rules. A user "mining" bitcoins is running a program that searches tirelessly for a solution to a very difficult math problem whose difficulty is precisely known. The difficulty is automatically adjusted regularly so that the number of solutions found globally, by everyone, is constant: an average of 6 per hour. When a solution is found, the user may tell everyone of the existence of this new found solution, along with other information, packaged together in what is called a "block". <br />
<br />
Blocks contain 50 bitcoins at present. This amount is an incentive for people to perform the computation work required for block generation. Roughly every 4 years, the number of bitcoins that can be "mined" in a block reduces by 50%. Any blocks that are created by a malicious user that do not follow this rule (or any other rules) will be rejected by everyone else. The result is that no more than 21 million bitcoins will ever exist. <br />
<br />
Because the "mining" incentive to put fourth the computational power to create blocks will eventually diminish, miners will some day pay for their hardware and electricity costs by collecting [[Transaction_fee|transaction fees]]. The sender of money may voluntarily pay a small transaction fee which will be kept by whoever finds the next block. Paying this fee will encourage the miner to include the transaction in a block more quickly.<br />
<br />
===Transferring a coin===<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
Suppose Alice wants to send a bitcoin to Bob.<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer to a message: a 'transaction' message.<br />
* Alice signs the transaction with her secret private key.<br />
* Alice broadcasts the transaction out over the bitcoin network for all to see.<br />
<br />
(Only the first step is actually completed by a human. The rest is done by the bitcoin client software.)<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her control.<br />
<br />
Later on, when Bob wishes to transfer the same bitcoin to Charley, he will do the same thing:<br />
* Charlie sends Bob his public key.<br />
* Bob adds Charlie's public key along with the amount he wants to transfer to a message: a 'transaction' message.<br />
* Bob signs the transaction with his private key.<br />
* Bob broadcasts the transaction out over the bitcoin network for all to see. <br />
<br />
Only Bob can do this because only Bob has the private key that corresponds to the public key Alice included in the previous transaction. <br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
===Preventing double-spending===<br />
The process described above does not prevent Alice from using a coin in more than one transaction. The following process does. This is the primary innovation behind Bitcoin.<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and it is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and is permanently recorded, preventing Alice from creating a second transaction with the same coin. In order for Alice to thwart this system and double-spend her coins, she would need to muster more computing power than all other bitcoin users combined.<br />
<br />
===Anonymity===<br />
There are no bitcoin "accounts" to set up. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. Transacting parties do not need to know each other's identity in the same way that a store owner does not know Bob's name is Bob when Bob goes and buys groceries with cash. <br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, which makes it very difficult to know which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. The Bitcoin software encourages this behavior by default. Continuing the example from above, when Charlie receives the bitcoin from Bob, Charlie will not be able to identify who owned the coin before Bob (not without asking Bob).<br />
<br />
You have completed reading our Bitcoin introduction!<br />
<br />
==Where to see and explore==<br />
You can directly explore the system in action by visiting the [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour which on average will be 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K).<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros. This what made making it so difficult; a hash that begins with many zeros is much more difficult to find than a hash with few or no zeros. The computer that generated this block had to try many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed. Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]<br />
<br />
[[zh-cn:简介]]<br />
<br />
[[de:Einführung]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=User:Prcarter&diff=8302User:Prcarter2011-05-13T04:56:59Z<p>Prcarter: </p>
<hr />
<div>Lending a hand.<br />
<br />
Contributors Award participant: 1FkDJjvm4uvQZN6KrP7ecCzZwkLa2bmbvo</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8225Help:Introduction2011-05-10T09:21:00Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and it is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and will be permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8224Help:Introduction2011-05-10T09:20:21Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* To be accepted in the chain, transaction blocks must be valid and must include [[proof of work]] (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and will be permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Proof_of_work&diff=8213Proof of work2011-05-10T00:57:50Z<p>Prcarter: </p>
<hr />
<div>{{stub}}<br />
<br />
A '''proof of work''' is a piece of data which was difficult (costly, time-consuming) to produce so as to satisfy certain requirements. It must be trivial to check whether data satisfies said requirements. Producing a proof of work can be a random process with low probability, so that a lot of trial and error is required ''on average'' before a valid proof of work is generated.<br />
<br />
One application of this idea is a proposed [http://en.wikipedia.org/wiki/Hashcash method for preventing email spam], requiring a proof of work on the email's contents (including the To address), on every email. Legitimate emails will be able to do the work to generate the proof easily (not much work is required for a single email), but mass spam emailers will have difficulty generating the required proofs (which would require huge computational resources).<br />
<br />
Proofs of work are used in Bitcoin for block generation. Proofs of work that are tied to the data of each block are required for the blocks to be accepted. The [[difficulty]] of this work is adjusted so as to limit the rate at which new blocks can be generated by the network to one every 10 minutes. Due to the very low probability of successful generation, this makes it unpredictable which worker computer in the network will be able to generate the next block.<br />
<br />
For a block to be valid it must hash to a value less than the current [[target]]; this means that each block indicates that work has been done generating it. Each block contains the hash of the preceeding block, thus each block has a [[block chain|chain]] of blocks that together contain a large amount of work. Changing a block (which can only be done by making a new block containing the same predecessor) requires regenerating all successors and redoing the work they contain. This protects the block chain from tampering.<br />
<br />
== Example ==<br />
<br />
Let's say the base string that we are going to do work on is "Hello, world!". Our target is to find a variation of it that SHA-256 hashes to a value beginning with '000'. We vary the string by adding a integer value to the end called a [[nonce]] and incrementing it each time. Finding a match for "Hello, world!" takes us 4251 tries (but happens to have zeroes in the first four digits):<br />
<br />
"Hello, world!0" => 1312af178c253f84028d480a6adc1e25e81caa44c749ec81976192e2ec934c64<br />
"Hello, world!1" => e9afc424b79e4f6ab42d99c81156d3a17228d6e1eef4139be78e948a9332a7d8<br />
"Hello, world!2" => ae37343a357a8297591625e7134cbea22f5928be8ca2a32aa475cf05fd4266b7<br />
...<br />
"Hello, world!4248" => 6e110d98b388e77e9c6f042ac6b497cec46660deef75a55ebc7cfdf65cc0b965<br />
"Hello, world!4249" => c004190b822f1669cac8dc37e761cb73652e7832fb814565702245cf26ebb9e6<br />
"Hello, world!4250" => 0000c3af42fc31103f1fdc0151fa747ff87349a4714df7cc52ea464e12dcd4e9<br />
<br />
4251 hashes on a modern computer is not very much work (most computers can achieve at least 4 million hashes per second). Bitcoin automatically varies the [[difficulty]] (and thus the amount of work required to generate a block) to keep a roughly constant rate of block generation. The probability of a single hash succeeding can be found [http://blockexplorer.com/q/probability here].<br />
<br />
In Bitcoin things are a bit more complex, especially since the header contains the [http://en.wikipedia.org/wiki/Merkle_tree Merkle tree] which depends on the included [[transactions]]. This includes the generation transaction, a transaction "out of nowhere" to our own address, which in addition to providing the miner with incentive to do the work, also ensures that every miner hashes a unique data set.<br />
<br />
[[Category:Vocabulary]]<br />
<br />
[[fr:Preuve de travail]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Proof_of_work&diff=8212Proof of work2011-05-10T00:56:13Z<p>Prcarter: </p>
<hr />
<div>{{stub}}<br />
<br />
A '''proof of work''' is a piece of data which was difficult (costly, time-consuming) to produce so as to satisfy certain requirements. It must be trivial to check whether data satisfies said requirements. Producing a proof of work can be a random process with low probability, so that a lot of trial and error is required ''on average'' before a valid proof of work is generated.<br />
<br />
One application of this idea is a proposed [http://en.wikipedia.org/wiki/Hashcash method for preventing email spam], requiring a proof of work on the email's contents (including the To address), on every email. Legitimate emails will be able to do the work to generate the proof easily (not much work is required for a single email), but mass spam emailers will have difficulty generating the required proofs (which would require huge computational resources).<br />
<br />
Proofs of work are used in Bitcoin for block generation. Proofs of work that are tied to the data of each block are required for the blocks to be accepted. The [[difficulty]] of this work is adjusted so as to limit the rate at which new blocks can be generated by the network to one every 10 minutes. Due to the very low probability of successful generation, makes it unpredictable which worker computer in the network will be able to generate the next block.<br />
<br />
For a block to be valid it must hash to a value less than the current [[target]]; this means that each block indicates that work has been done generating it. Each block contains the hash of the preceeding block, thus each block has a [[block chain|chain]] of blocks that together contain a large amount of work. Changing a block (which can only be done by making a new block containing the same predecessor) requires regenerating all successors and redoing the work they contain. This protects the block chain from tampering.<br />
<br />
== Example ==<br />
<br />
Let's say the base string that we are going to do work on is "Hello, world!". Our target is to find a variation of it that SHA-256 hashes to a value beginning with '000'. We vary the string by adding a integer value to the end called a [[nonce]] and incrementing it each time. Finding a match for "Hello, world!" takes us 4251 tries (but happens to have zeroes in the first four digits):<br />
<br />
"Hello, world!0" => 1312af178c253f84028d480a6adc1e25e81caa44c749ec81976192e2ec934c64<br />
"Hello, world!1" => e9afc424b79e4f6ab42d99c81156d3a17228d6e1eef4139be78e948a9332a7d8<br />
"Hello, world!2" => ae37343a357a8297591625e7134cbea22f5928be8ca2a32aa475cf05fd4266b7<br />
...<br />
"Hello, world!4248" => 6e110d98b388e77e9c6f042ac6b497cec46660deef75a55ebc7cfdf65cc0b965<br />
"Hello, world!4249" => c004190b822f1669cac8dc37e761cb73652e7832fb814565702245cf26ebb9e6<br />
"Hello, world!4250" => 0000c3af42fc31103f1fdc0151fa747ff87349a4714df7cc52ea464e12dcd4e9<br />
<br />
4251 hashes on a modern computer is not very much work (most computers can achieve at least 4 million hashes per second). Bitcoin automatically varies the [[difficulty]] (and thus the amount of work required to generate a block) to keep a roughly constant rate of block generation. The probability of a single hash succeeding can be found [http://blockexplorer.com/q/probability here].<br />
<br />
In Bitcoin things are a bit more complex, especially since the header contains the [http://en.wikipedia.org/wiki/Merkle_tree Merkle tree] which depends on the included [[transactions]]. This includes the generation transaction, a transaction "out of nowhere" to our own address, which in addition to providing the miner with incentive to do the work, also ensures that every miner hashes a unique data set.<br />
<br />
[[Category:Vocabulary]]<br />
<br />
[[fr:Preuve de travail]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8207Help:Introduction2011-05-09T23:33:19Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Transaction blocks must be valid and must include [[proof of work]] to be accepted in the chain (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and is then extended further.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and will be permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8206Help:Introduction2011-05-09T23:31:55Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Transaction blocks must be valid and must include [[proof of work]] to be accepted in the chain (one block generated by the network every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and extended.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and will be permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8205Help:Introduction2011-05-09T23:28:45Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Transaction blocks must be valid and must include [[proof of work]] to be accepted in the chain (one block generated by someone every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, only the longest such branch is accepted and extended.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the single longest and fastest-growing block chain (extended with significant computational effort), he can be confident that the transaction by Alice has been accepted by the computers in the network and will be permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8204Help:Introduction2011-05-09T23:16:35Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Transaction blocks must be valid and must include [[proof of work]] to be accepted in the chain (one block generated by someone every 10 minutes).<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8203Help:Introduction2011-05-09T23:10:22Z<p>Prcarter: /* Creation of coins */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks require [[proof of work]] to be accepted in the chain, and must contain valid transactions.<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This amount is an incentive for people to perform the computation work required for block generation. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount. The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8202Help:Introduction2011-05-09T22:58:37Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks require [[proof of work]] to be accepted in the chain, and must contain valid transactions.<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=8201Help:Introduction2011-05-09T22:56:24Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same number of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction (this is the main innovation behind Bitcoin):<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks require [[proof of work]] to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way so that, if any one is modified, all following blocks will have to be recomputed.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=7721Help:Introduction2011-04-26T13:05:05Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same amount of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction:<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks are computationally difficult to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way that does not allow their data to be modified, without all following blocks becoming invalid.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction, as only the longest chain is accepted. To remain the longest, it also has to grow faster than any other chain, so as to prevent any block generator from adding Alice's transaction to the chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control a majority of the CPUs are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=7720Help:Introduction2011-04-26T12:58:39Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same amount of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction:<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks are computationally difficult to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way that does not allow their data to be modified, without all following blocks becoming invalid.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. The only way for Alice to remove her transaction is to create a parallel chain which is longer than the one generated by everybody else and which doesn't contain her transaction. To remain the longest, it also has to grow faster than any other chain. To do that, Alice has to be in a position to permanently command the majority of the CPU power on the network; something we assume no single person or organization can do. Therefore, as long as the people who control the majority of the CPUs on the network are not cooperating with Alice, her transaction will be permanently recorded and she will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=7676Help:Introduction2011-04-25T13:12:02Z<p>Prcarter: /* Preventing double-spending */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same amount of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction:<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks are computationally difficult to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way that does not allow their data to be modified, without all following blocks becoming invalid.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been permanently recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. And since, in the presence of multiple parallel chains of blocks of transactions, the longest such chain is accepted and built upon, the only way for Alice to pass her own version of events is to be in a position to permanently command the majority of the CPU power on the network. We assume no single person or organization can do that and therefore, as long as the people who control the majority of the CPU power are acting honestly, accepting only valid blocks and always choosing the longest chain as the one to extend, Alice's transaction will be permanently recorded and Alice will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=7674Help:Introduction2011-04-25T12:51:18Z<p>Prcarter: /* Anonymity */</p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same amount of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction:<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks are computationally difficult to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way that does not allow their data to be modified, without all following blocks becoming invalid.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. And since, in the presence of multiple parallel chains of blocks of transactions, the longest such chain is accepted and built upon, the only way for Alice to pass her own version of events is to be in a position to permanently command the majority of the CPU power on the network. We assume no single person or organization can do that and therefore, as long as the people who control the majority of the CPU power are acting honestly, accepting only valid blocks and always choosing the longest chain as the one to extend, Alice's transaction will be permanently recorded and Alice will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A [[Address|Bitcoin address]] mathematically corresponds to a public key and looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such addresses, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions (not without asking Charley).<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=7673Help:Introduction2011-04-25T12:19:38Z<p>Prcarter: </p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same amount of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting with customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction:<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks are computationally difficult to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way that does not allow their data to be modified, without all following blocks becoming invalid.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. And since, in the presence of multiple parallel chains of blocks of transactions, the longest such chain is accepted and built upon, the only way for Alice to pass her own version of events is to be in a position to permanently command the majority of the CPU power on the network. We assume no single person or organization can do that and therefore, as long as the people who control the majority of the CPU power are acting honestly, accepting only valid blocks and always choosing the longest chain as the one to extend, Alice's transaction will be permanently recorded and Alice will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A bitcoin [[Address|address]] looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such key pairs, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions. The only thing David will know is the address of Bob which is a shortened (hashed) version of his public key.<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Help:Introduction&diff=7672Help:Introduction2011-04-25T12:19:29Z<p>Prcarter: </p>
<hr />
<div>Alice is far away from Bob and wants to buy his [http://www.grasshillalpacas.com/alpacaproductsforbitcoinoffer.html Alpaca socks]. In return, she wants to send him a dollar. A dollar bill is a piece of paper which is very easy to create (by those who can), but which is accepted by people in exchange for valuable products and services in the real world, such as the socks Alice wants to buy. One simple thing Alice can do is to put a dollar bill in an envelope, mail it to Bob, and then wait for Bob to send the socks to her.<br />
<br />
Another thing Alice can do is to "wire" the money to Bob. She can do that by first giving her dollar bills to an institution called a bank, the job of which is to safe-keep Alice's dollar bills and, in return, to give Alice a written promise (called a "bank statement") that, whenever she wishes, she can come to the bank to take back the same amount of dollar bills that she deposited. Since the money is still Alice's, she is entitled to do with it whatever she pleases, and the bank (like most banks), for a small fee, will do Alice the service of "giving" the dollar bills to Bob instead of her. This could be done by sending a person to Bob's door, with Alice's dollar bills in hand (or, better, fresh new dollar bills, if Alice's dollar bills are in bad condition), but usually it is done by Alice's bank by giving the dollar bills to Bob's bank and informing them that the money is for Bob, who will then see the amount in his next statement, or, if he is in a hurry, the next time he contacts his bank asking about how much money they have for him.<br />
<br />
Since banks have many customers, and bank employees require money for doing the job of talking to people and signing documents, banks in recent times have been using machines such as ATMs and web servers, that do the job of interacting customers instead of paid bank employees. The job of these machines is to learn what each customer wants to do with his/her money and, to the extent that it's possible, act on what the customer wants (for example, ATMs can hand cash). In the end, there is very little human involvement in this process, most of the time. The people can always know how much money out of the money that the bank is safe-keeping is theirs, and they are confident that the numbers they see in their bank statements and on their computer screens stand for the number of dollar bills that that they can get from the bank at any time they wish. They can be so sure of that, that they can accept those numbers in the same way they accept paper dollars (this is similar to the way people started accepting paper dollars as they accepted gold or silver).<br />
<br />
However, the fact that machines are used does not change the structure of this system, which is, as it was, based on a central authority (the bank) which is responsible for keeping records about how much money belongs to whom. Everybody has to rely on this central authority to be honest (i.e. to say the truth about how much money they are safe-keeping in total, or at least to make the paper money available upon demand from the owners). Also, every person has to identify him/herself to this authority, by giving his/her real name, in order to be allowed to get their paper bills back or to send money to another person.<br />
<br />
Bitcoin is a system of owning and voluntarily transferring amounts of so-called bitcoins, in a manner similar to an on-line banking interface, but anonymously and without reliance on a central authority to decide on what is true. These bitcoins are valuable because they require the spending of real resources (CPU time and electricity) to produce, cannot be spent more than once, and cannot be removed from a person's ownership without illicit access to his/her computer.<br />
<br />
==Preventing stealing==<br />
To guarantee that an eavesdropper, Eve, cannot access other people's bitcoins by creating transactions in their names we use a [[Wikipedia:Public-key_cryptography|public key system]] to make digital signatures. In this system, each person, such as Alice and Bob, has a pair of public and private keys which he/she stores in a safe [[Wallet|wallet]]. Only the user with his secret private key can sign a document, such as the transaction to give some of his bitcoins to somebody else, but any one can validate the signature using the user’s public key.<br />
<br />
* Bob sends his public key to Alice.<br />
* Alice adds Bob’s public key along with the amount she wants to transfer, to the transaction.<br />
* Alice signs the transaction with her secret private key.<br />
<br />
As a result, anyone who knows the public keys of both Alice and Bob can now see that Alice agreed to transfer the amount to Bob, because nobody other than Alice has Alice's private key. Alice would be foolish to give her private key to other people, as this would allow them to sign transactions in her name, removing funds from her balance.<br />
<br />
Later on, when Bob will transfer the same coins to Charley, he will do the same thing: receive from Charley his public key, add a new transaction to the chain of transactions and sign it with his (Bob) private key. But only Bob can do this, because only Bob has the private key which is necessary for signing and which is the only private key to match Bob’s public key that is already in the chain.<br />
<br />
Eve cannot change who the coins belong to by replacing Bob’s public key with her public key, because Alice signed the transfer to Bob using her private key, declaring that the coins which belonged to her now belong to Bob, and Alice's private key is kept secret from Eve. So if Charley accepts that the original coin was in the hands of Alice he will also accept the fact that this coin was later passed to Bob and now Bob is passing this same coin to him.<br />
<br />
==Preventing double-spending==<br />
This is how we guarantee that Alice cannot replicate the coin and use it in more than one transaction:<br />
<br />
* Details about the [[Transactions|transaction]] are [[Network|sent and forwarded]] to all or as many other computers as possible.<br />
* A constantly growing chain of [[Blocks|blocks]] that contains a record of all transactions is collectively maintained by all computers (each has a full copy).<br />
* Valid blocks are computationally difficult to create and only valid blocks are allowed in the chain, containing valid transactions.<br />
* Blocks are chained in a way that does not allow their data to be modified, without all following blocks becoming invalid.<br />
* When multiple valid continuations to this chain appear, the longest such branch is accepted as the correct one and built upon.<br />
<br />
When Bob sees that his transaction has been included in a block, which has been made part of the longest and constantly growing block chain, he can be confident that the transaction by Alice has been accepted by other computers as valid and has been recorded, preventing Alice from creating a second transaction with the same coin.<br />
<br />
In theory, Alice could attempt to generate spoofed blocks in which her past usage of the same coin does not appear and try to send these blocks to everyone as evidence that the coin is still hers. However, that past transaction, which contains a signature from Alice, has already been announced, has already been distributed to a very large number of computers in the bitcoin network and a block containing it has already been generated by someone (otherwise, the first receiver of the coin would have no confirmation). Since the process of generating a valid block is designed to take a [[Proof_of_work|long time]], Alice will be unable to compete with all these computers in the rate at which she can generate blocks. Bob will receive many more blocks from third persons than Alice alone will ever be able to generate, and some of the newer blocks will contain Alice's previous transaction, telling Bob that Alice has already spent her coin. And since, in the presence of multiple parallel chains of blocks of transactions, the longest such chain is accepted and built upon, the only way for Alice to pass her own version of events is to be in a position to permanently command the majority of the CPU power on the network. We assume no single person or organization can do that and therefore, as long as the people who control the majority of the CPU power are acting honestly, accepting only valid blocks and always choosing the longest chain as the one to extend, Alice's transaction will be permanently recorded and Alice will be unable to create another transaction with the same coin.<br />
<br />
==Anonymity==<br />
Bitcoin "accounts" do not have people's names on them and do not have to correspond to individuals. Each balance is simply associated with a randomly generated public-private key pair and the money "belongs" to whoever has the private key and can sign transactions with it. The transactions that are signed using those keys also don't have to include names.<br />
<br />
A bitcoin [[Address|address]] looks like this:<br />
<br />
:15VjRaDX9zpbA8LVnbrCAFzrVzN7ixHNsC<br />
<br />
Each person can have many such key pairs, each with its own balance, and this can make it more difficult to identify which person owns what amount. In order to protect his [[Anonymity|privacy]], Bob can even generate a new public-private key pair for each individual transaction. So David receiving the coin from Charley will not be able to identify who is the second person in the list of transactions. The only thing David will know is the address of Bob which is a shortened (hashed) version of his public key.<br />
<br />
==Creation of coins==<br />
As we saw, both Bob and Charley need to verify that the original coin from Alice is valid. Alice cannot simply generate coins instantly, out of thin air, because the appearance of a coin is a transaction that needs to be accepted by others. In order for the coin-creation transaction to be accepted, the transaction and the block in which it appears must be part of the longest chain of blocks. For new blocks to be added as continuations to this coin-generating block, it must be considered valid by those who generate blocks. For the chain to remain the longest, the speed at which blocks are added to it must be faster than that of any other chain. Therefore, for the coin-generating transaction to exist, it must be considered valid by the software that is running on the majority of the CPUs on the network.<br />
<br />
According to current software, the way that new coins are slowly introduced is this: every computer that manages to generate a block is allowed to put one transaction there in which it gains 50 BTC, without this amount having to come from somewhere. This is called a "proof of work", because generating blocks is a [[Target|slow]] process that requires Alice to spend real resources (buy recent computer hardware, use electricity and CPU time) and in this way it can be compared to gold mining. Only with a proof of work is Alice allowed to contribute to the [[Block_chain|chain of blocks]] that together keep a record of all transactions.<br />
<br />
The coin received by Alice is an incentive for her to perform this computation work. However, it is currently agreed that the reward for generating a block will be reduced to half every 4 years. Meaning that, at some point in the year 2013, the majority of the CPUs will stop accepting blocks in which the generating transaction adds 50BTC to the sum of money, and they will only accept blocks adding half that amount (or less?). The same thing will happen in the years 2017, 2021, 2025 and so on, unless different Bitcoin client software has prevailed in the network.<br />
<br />
Since this incentive will eventually diminish, another way for Alice to gain bitcoins when she generates blocks is to accept [[Transaction_fee|transaction fees]]. There is a voluntary transaction fee that can be paid in every transfer of bitcoins, the amount of which is chosen, and paid, by the person who sends the money. This amount is given to the person who generates the "proof-of-work" block in which the transaction appears, which is necessary for the transaction to be accepted. Since Alice is free to include in her block whichever set of transactions she wants, she can choose to include only the transactions with the highest transaction fees. If everybody acts that way, then eventually, and depending on the total number of transactions, a minimum transaction fee will be required for a transaction to appear in the chain of blocks.<br />
<br />
==Putting it all together==<br />
Directly experience the system in action by visiting [http://blockexplorer.com/ Bitcoin Block Explorer].<br />
The site shows you the latest blocks in the block chain. The [[Block_chain|block chain]] contains the agreed history of all transactions that took place in the system.<br />
Note how many blocks were generated in the last hour, should be around 6. Also notice the number of transactions and the total amount transferred in the last hour (last time I checked it was about 64 and 15K.)<br />
This should give you an indication of how active the system is.<br />
<br />
Next, drill into one of these blocks.<br />
Start by noticing that the block's [[hash|hash]] begins with a run of zeros, this is what made making it so difficult.<br />
The computer that generated this block had to run on many ''Nonce'' values (also listed on the block's page) until it found one that generated this run of zeros.<br />
Next notice the line titled ''Previous block'', each block contains the hash of the block that came before it, this is what forms the chain of blocks.<br />
Now notice all the transactions the block contains. The first transaction is the income earned by the computer that generated this block. It includes a fixed amount of coins created out of thin air and possibly fee collected from other transactions in the same block.<br />
<br />
Drill into any of the transactions and you will see how it is made from one or more amounts coming in and out.<br />
The fact that there can be more than one incoming and outgoing amounts, allow the system to join and break amounts in any possible way allowing for any fractional amount needed (usually cents.)<br />
Each incoming amount is a transaction from the past (which you can also drill to) coming from an address of someone<br />
and each outgoing amount is addressed to someone and will be part of a future transaction (which you can also drill too if it also had already taken place.)<br />
<br />
Finally you can drill into any of the [[Address|addresses]] and see what public information is available.<br />
<br />
To get an impression of the amount of activity on the Bitcoin network, you might like to visit the monitoring websites [[Bitcoin Watch]] and [[Bitcoin Monitor]]. The first has general statistics on the amount and size of transactions, while the latter shows a real-time visualization of events on the Bitcoin network.<br />
<br />
''So that all sounds good! How do I help? [[Helping Bitcoin|How to help Bitcoin]]''<br />
<br />
==See Also==<br />
<br />
* [http://www.youtube.com/watch?v=Um63OQz3bjo What is Bitcoin?] video introduction<br />
* Installing Bitcoin [[getting started]] <br />
* [[How bitcoin works]]<br />
* [[Using Bitcoin]]<br />
* A gentle introduction to Bitcoin - [[BitcoinMe]]<br />
* Another introduction, ''The Rebooting Of Money'' podcast is found at [[Bitcoin Money]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Currency_exchange&diff=6620Currency exchange2011-04-02T19:36:07Z<p>Prcarter: </p>
<hr />
<div>Bitcoin currency exchanges work in a manner similar to banks. One first deposits amounts of money in the currencies supported by the exchange, to his own account in the exchange, uses these balances to trade with other users of the exchange and then withdraws that money. Unlike over-the-counter transactions, there is no risk of losing money due to people not fulfilling their part of the deal, as long as the exchange itself does not commit fraud or withhold money.<br />
<br />
Exchanging is done by placing "buy" or "sell" orders, which the exchange system software then matches with each other. "Buy" orders (or "bids") are offers to buy bitcoins in exchange for another currency at a maximum price-per-bitcoin which is set by the offerer. "Sell" orders (or "asks") are offers to sell bitcoins at a minimum price-per-bitcoin. If the bid price of a buy order is higher than the ask price of a sell order, an exchange can be performed and either the bid order, the sell order or both can be removed from the "order book". Thus, at any given time, there is a price above which there are no more buy orders and a slightly higher price below which there are no more sell orders.<br />
<br />
Communication with the Bitcoin currency exchanges is commonly done using a standard web browser, over a secure SSL connection.<br />
<br />
The payment methods that are most commonly accepted and used by Bitcoin currency exchanges are:<br />
<br />
* Bitcoin transfers<br />
* Liberty Reserve<br />
* Bank wires<br />
* Credit cards<br />
<br />
Currencies that can be exchanged with Bitcoins in an automated way include:<br />
<br />
* US Dollars<br />
* Euros<br />
* Japanese Yen<br />
* Russian Rubles<br />
* Pound Sterling<br />
* Pecunix Gold<br />
<br />
=="Soft currencies" and chargebacks==<br />
<br />
Exchanging bitcoins for other forms of currency brings up some issues regarding chargeback fraud. Specifically, payment methods such as credit cards, and PayPal, can be reversed up to 90 days after the transaction took place. In contrast, bitcoin is a "hard currency", once you spend bitcoins, you cannot get them back by 'pulling' from your side. Thus, when you trade bitcoin for a 'soft' currency like paypal or credit card, you open yourself up to the risk of chargeback after you send bitcoin. The buyer may initiate a chargeback by claiming non-receipt of goods, or if a stolen account was used, the real account owner will initiate the process once he notices a charge he didn't make. As a result, it is strongly recommended to not trade 'soft' currency for 'hard' currency with people you do not know or trust. <br />
<br />
In January, 2010, an open source currency exchange platform was released by the founder of [[Bitcoin Central]]<ref>[http://www.bitcoin.org/smf/index.php?topic=2585.0 Bitcoin Central going open source ! Open your own trading site for free !]</ref>.<br />
<br />
The two major exchanges at the time, [[Bitcoin Market]] and [[Mtgox]], were hit with a wave of PayPal scams in October 2010, where one or a group of individuals used stolen PayPal accounts to fund their exchange accounts to buy bitcoins. This has caused the freezing of the Mtgox paypal account<ref>http://www.bitcoin.org/smf/index.php?topic=1419.0</ref>, and a suspension of new user registration on [[Bitcoin Market]]<ref>http://www.bitcoin.org/smf/index.php?topic=1461.0</ref>. These account freezes caused a temporary liquidity problem for the bitcoin economy, as it became more difficult to exchange dollars for bitcoins.<br />
<br />
==See also==<br />
<br />
* [[:Category:Exchanges|Exchanges]]<br />
* [[Buying bitcoins]]<br />
<br />
==References==<br />
<references/><br />
<br />
[[Category:Exchanges]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Currency_exchange&diff=6619Currency exchange2011-04-02T19:19:55Z<p>Prcarter: </p>
<hr />
<div>{{stub}}<br />
<br />
Bitcoin currency exchanges work in a manner similar to banks. One first deposits amounts of money in the currencies supported by the exchange, to his own account in the exchange, uses these balances to trade with other users of the exchange and then withdraws that money. Unlike over-the-counter transactions, there is no risk of losing money due to people not fulfilling their part of the deal, as long as the exchange itself does not commit fraud or withhold money.<br />
<br />
Exchanging is done by placing "buy" or "sell" orders, which the exchange system software then matches with each other. "Buy" orders (or "bids") are offers to buy bitcoins in exchange for another currency at a maximum price-per-bitcoin which is set by the offerer. "Sell" orders (or "asks") are offers to sell bitcoins at a minimum price-per-bitcoin. If the bid price of a buy order is higher than the ask price of a sell order, an exchange can be performed and either the bid order, the sell order or both can be removed from the "order book". Thus, at any given time, there is a price above which there are no more buy orders and a slightly higher price below which there are no more sell orders.<br />
<br />
Communication with the Bitcoin currency exchanges is commonly done using a standard web browser, over a secure SSL connection.<br />
<br />
The payment methods that are most commonly accepted and used by Bitcoin currency exchanges are:<br />
<br />
* Bitcoin transfers<br />
* Liberty Reserve<br />
* Bank wires<br />
* Credit cards<br />
<br />
=="Soft currencies" and chargebacks==<br />
<br />
Exchanging bitcoins for other forms of currency brings up some issues regarding chargeback fraud. Specifically, payment methods such as credit cards, and PayPal, can be reversed up to 90 days after the transaction took place. In contrast, bitcoin is a "hard currency", once you spend bitcoins, you cannot get them back by 'pulling' from your side. Thus, when you trade bitcoin for a 'soft' currency like paypal or credit card, you open yourself up to the risk of chargeback after you send bitcoin. The buyer may initiate a chargeback by claiming non-receipt of goods, or if a stolen account was used, the real account owner will initiate the process once he notices a charge he didn't make. As a result, it is strongly recommended to not trade 'soft' currency for 'hard' currency with people you do not know or trust. <br />
<br />
In January, 2010, an open source currency exchange platform was released by the founder of [[Bitcoin Central]]<ref>[http://www.bitcoin.org/smf/index.php?topic=2585.0 Bitcoin Central going open source ! Open your own trading site for free !]</ref>.<br />
<br />
The two major exchanges at the time, [[Bitcoin Market]] and [[Mtgox]], were hit with a wave of PayPal scams in October 2010, where one or a group of individuals used stolen PayPal accounts to fund their exchange accounts to buy bitcoins. This has caused the freezing of the Mtgox paypal account<ref>http://www.bitcoin.org/smf/index.php?topic=1419.0</ref>, and a suspension of new user registration on [[Bitcoin Market]]<ref>http://www.bitcoin.org/smf/index.php?topic=1461.0</ref>. These account freezes caused a temporary liquidity problem for the bitcoin economy, as it became more difficult to exchange dollars for bitcoins.<br />
<br />
==See also==<br />
<br />
* [[:Category:Exchanges|Exchanges]]<br />
* [[Buying bitcoins]]<br />
<br />
==References==<br />
<references/><br />
<br />
[[Category:Exchanges]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Category:History&diff=6608Category:History2011-04-02T18:04:21Z<p>Prcarter: </p>
<hr />
<div>* October 31, 2008<br />
** [http://article.gmane.org/gmane.comp.encryption.general/12588/ Bitcoin design paper] published<br />
* November 09, 2008<br />
** Bitcoin project registered at SourceForge.net<br />
* January 3, 2009<br />
** Genesis block established at 18:15:05 GMT<br />
* January 11, 2009<br />
** Bitcoin v0.1 released and announced on the [http://www.mail-archive.com/cryptography@metzdowd.com/msg10152.html cryptography mailing list]<br />
* December 16, 2009<br />
** Bitcoin v0.2 released<br />
* December 30, 2009<br />
** First difficulty increase at 06:11:04 GMT<br />
* February 6, 2010<br />
** [[Bitcoin Market]] established<br />
* May 22, 2010<br />
** lazslo first to buy pizza with Bitcoins [http://www.bitcoin.org/smf/index.php?topic=137.msg1195#msg1195 agreeing] upon paying 10,000btc for ~$25 worth of pizza courtesy of jercos<br />
* July 7, 2010<br />
** Bitcoin v0.3 released<br />
* July 11, 2010<br />
** Bitcoin v0.3 release [http://news.slashdot.org/story/10/07/11/1747245/Bitcoin-Releases-Version-03 mentioned on slashdot], bringing a large influx of new bitcoin users.<br />
* July 17, 2010<br />
** [[MtGox]] established<br />
* July 18, 2010<br />
** ArtForz generated his first block after establishing his personal OpenCL GPU hash farm<br />
* August 15, 2010<br />
** [[Incidents#Value_overflow|74638]]<br />
* September 14, 2010<br />
** jgarzik [http://www.bitcoin.org/smf/index.php?topic=133.msg12921#msg12921 offered] 10,000btc (valued at ~$600-650) to puddinpop to open source their windows-based CUDA client<br />
* September 18, 2010<br />
** puddinpop [http://www.bitcoin.org/smf/index.php?topic=133.msg13135#msg13135 released] source to their windows-based CUDA client under MIT license<br />
* September 29, 2010<br />
** kermit [http://www.bitcoin.org/smf/index.php?topic=1306.0 discovered] a microtransactions exploit which precipitated the Bitcoin v0.3.13 release<br />
* October 01, 2010<br />
** First public OpenCL miner released<br />
* October 04, 2010<br />
** Original Bitcoin History wiki page (this page) established (ooh so meta) on Bitcoin.org's wiki.<br />
* October 28, 2010<br />
** First bitcoin short sale transaction initiated, with a loan of 100 BTC by nanotube to [[User:Kiba|kiba]], facilitated by the [[Bitcoin-otc|#bitcoin-otc]] market.<br />
* November 6, 2010<br />
** The [http://www.bitcoin.org/smf/index.php?topic=1672 Bitcoin economy passed US $1 million]. The MtGox price touched USD $0.50.<br />
* December 7, 2010<br />
** Bitcoind was compiled for the Nokia N900 mobile computer by doublec. The following day, ribuck sent him 0.42 BTC in the first portable-to-portable Bitcoin transaction.<br />
* December 9, 2010<br />
** The generation difficulty passed 10,000.<br />
** First bitcoin call option contract sold, from nanotube to [[User:Sgornick|sgornick]], via the [[Bitcoin-otc|#bitcoin-otc]] market.<br />
* December 16, 2010<br />
** [http://mining.bitcoin.cz/ Bitcoin Pooled Mining], operated by slush, found its first block<br />
* January 2, 2011<br />
** [[Tonal BitCoin]] units standardized.<br />
* January 8, 2011<br />
** [[History of Bitcoin]] page (this page) created after replicating from original Bitcoin History page on Bitcoin.org.<br />
** Bitcoin Pooled Mining reached a total of 10,000 Mhash/s<br />
* January 27, 2011<br />
** Largest numeric value ever traded for bitcoins thus far occurred on this date. Three currency bills from Zimbabwe, known as Zimdollars, were traded on [[Bitcoin-otc|#bitcoin-otc]] at the rate of 4 BTC for each of the one-hundred trillion dollar ($100,000,000,000,000) Zimbabwe notes<ref>Serial numbers for Zimdollars sold: AA1669317, AA1669318 and AA1669319</ref><br />
* January 28, 2011<br />
** Block 105000 was generated. This means that 5.25 million bitcoins have been generated, which is just over one-quarter of the eventual total of nearly 21 million.<br />
* February 9, 2011<br />
** Decimal Bitcoin reached parity with the US dollar, touching $1 per BTC at [[MtGox]].<br />
* February 10, 2011<br />
** Bitcoin.org website struggles to handle [http://www.bitcoin.org/smf/index.php?topic=3444.0 traffic] resulting from mentions on Slashdot<ref>[http://news.slashdot.org/story/11/02/10/189246/Online-Only-Currency-BitCoin-Reaches-Dollar-Parity Online-Only Currency BitCoin Reaches Dollar Parity]</ref>, Hacker News and Twitter following the news that parity had been reached.<br />
* February 14, 2011<br />
** A vehicle was, for the first time, offered in exchange for a certain number of bitcoins<ref>[http://www.bitcoin.org/smf/index.php?topic=3485.0 Car for Sale - Australia]</ref>.<br />
* March 6, 2011<br />
** Total Bitcoin network computation speed for a short time [http://bitcoin.sipa.be/speed-lin.png reached an all-time high of almost 900Ghash/sec], dropping to 500Ghash/sec soon after. Some speculate that this was due to some supercomputer or bot-net that joined the network ([http://bitcoin.atspace.com/mysteryminer.html mystery miner]).<br />
* March 18, 2011<br />
** BTC/USD exchange rate reaches a 6-week low point at almost $0.70/BTC, after what appeared to be a short burst of, possibly automated, BTC sales at progressively lower prices. BTC price had been declining since the February 9 high.<br />
* March 25, 2011<br />
** Difficulty decreased nearly 10%. A decrease has only occurred once before, and this decrease of nearly 10% was the largest.<br />
* March 27, 2011<br />
** The first market for exchanging bitcoins to and from the British Pound Sterling BTC/GBP, Britcoin, opens.<br />
<br />
{{fromold|bitcoin_history}}<br />
<br />
==References==<br />
<references /></div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Myths&diff=6363Myths2011-03-30T04:27:19Z<p>Prcarter: /* Fractional reserve banking is not possible */</p>
<hr />
<div>Lets clear up common Bitcoin misconceptions.<br />
<br />
<br />
<br />
== Bitcoins don't solve any problems that fiat and/or gold doesn't solve ==<br />
<br />
Unlike gold, bitcoins are:<br />
* easy to transfer and store<br />
* easy to verify authenticity<br />
<br />
Unlike fiat currencies, bitcoins are:<br />
* predictable, and decreasing, as far as the rate of monetary inflation<br />
* not controlled by a central authority<br />
<br />
Unlike electronic fiat currency systems, bitcoins are:<br />
* potentially anonymous<br />
* assets cannot be frozen<br />
<br />
== Bitcoin is backed by CPU cycles ==<br />
<br />
It is not correct to say that Bitcoin is backed by CPU power. A currency being "backed" by something means that it is pegged to something else via a central party at a certain exchange rate. You cannot exchange bitcoins for the computing power that was used to create them. Bitcoin is in this sense not backed by anything. It is a commodity in its own right. Similar to gold - is gold backed by anything? No! It's just gold. Same thing with bitcoin. <br />
<br />
The Bitcoin currency is ''created'' via processing power, and the integrity of the block chain is ''protected'' by the existence of a large network of computing nodes from certain possible [[Weaknesses#Attacker_has_a_lot_of_computing_power|attacks]] exists. And that is all.<br />
<br />
== Bitcoins are worthless because they aren't backed by anything ==<br />
<br />
Gold isn't backed by anything either. See myth https://en.bitcoin.it/wiki/Myths#Bitcoin_is_backed_by_CPU_cycles<br />
<br />
== Bitcoins value is based on how much electricity and computing power it takes to mine them ==<br />
<br />
This statement is an attempt to apply to bitcoin the [http://en.wikipedia.org/wiki/Labor_theory_of_value labor theory of value], which is generally accepted as false. Just because something takes X resources to create does not mean that the resulting product will be worth X. It can be worth more, or less, depending on the utility thereof to its users. <br />
<br />
In fact the causality is the reverse of that (this applies to the labor theory of value in general). The cost to mine bitcoins is based on how much they are worth. If bitcoins go up in value, more people will mine (because mining is profitable), thus [difficulty] will go up, thus the cost of mining will go up. The inverse happens if bitcoins go down in value. These effects balance out to cause mining to always cost the amount of bitcoins it produces.<br />
<br />
== Bitcoins have no intrinsic value (unlike some other things) ==<br />
<br />
It is true that bitcoins have no intrinsic value, in other words, value in any realm outside of being used as a medium of exchange.<br />
<br />
However, while some tangible commodities do have intrinsic value, that value is generally much less than its trading price. Consider for example that gold, if it were not used as an inflation-proof store of value, but rather only for its industrial uses, would certainly not be worth what it is today, since the industrial requirements for gold are far smaller than the available supply thereof.<br />
<br />
While historically intrinsic value, as well as other attributes like divisibility, fungibility, scarcity, durability, helped establish certain commodities as mediums of exchange, it is certainly not a prerequisite. While bitcoins lack 'intrinsic value', they make up for it in spades by possessing the other qualities necessary to make it a good medium of exchange.<br />
<br />
Value is ultimately determined by what people are willing to trade for - by supply and demand.<br />
<br />
Alternatively, bitcoins do have intrinsic value because they are divisible, fungible, scarce commodities.<br />
<br />
Alternatively, nothing has intrinsic value.<br />
<br />
People decide to hold bitcoins for a variety of reasons. One possible argument in favor of doing so is that <br />
bitcoin is a bookkeeping system and that having bitcoins is a proof of creditworthiness. Another argument is based <br />
on the analogy with precious metals, which share many properties of bitcoins like divisibility and easy <br />
transferability. --blablaa@freenode<br />
<br />
== Bitcoins are illegal because it's not legal tender ==<br />
<br />
Short answer: chickens aren't legal tender either, but bartering with chickens is not illegal.<br />
<br />
There are a [http://en.wikipedia.org/wiki/Local_currency number of currencies] in existence that are not official government-backed currencies. A currency is, after all, nothing more than a convenient unit of account. While national laws may vary from country to country, and you should certainly check the laws of your jurisdiction, in general trading in any commodity, including digital commodities like bitcoin, game currencies like WoW gold or Linden dollars, is not illegal.<br />
<br />
== Bitcoin is a form of domestic terrorism because it only harms the economic stability of the USA and its currency ==<br />
<br />
http://en.wikipedia.org/wiki/Definitions_of_terrorism#United_States according to this, you need to do violent activities to be considered a terrorist for legal purposes. This has no bearing on politicians and idiotic US attorney's public remarks.<br />
<br />
Also bitcoin isn't domestic. It's a worldwide community. See this map of bitcoin nodes <br />
http://www.bitcoin.org/smf/index.php?topic=2346.0<br />
<br />
== Bitcoin will only enable tax evaders which will lead to the eventual downfall of civilization ==<br />
<br />
It's up to you to follow the applicable state laws in your home country, or face the consequences.<br />
<br />
== Bitcoins can be printed/minted by anyone and are therefore worthless ==<br />
<br />
It requires substantial computing power to generate new coins, and eventually all the coins will be generated.<br />
<br />
== Bitcoins are worthless because it's based on unproven cryptography ==<br />
<br />
SHA256 and ECDSA which are used in Bitcoin are well-known industry standard algorithms.<br />
<br />
== Early adopters are unfairly rewarded ==<br />
<br />
Early adopters are rewarded for taking the higher risk with their time and money. <br />
<br />
In more pragmatic terms, "fairness" is an arbitrary concept that is improbable to be agreed upon by a large population. Establishing "fairness" is no goal of Bitcoin, as this would be impossible.<br />
<br />
The vast majority of the 21 million Bitcoins still have not been distributed. By starting to mine or acquire Bitcoins today, you too can become an early adopter.<br />
<br />
== 21 million coins isn't enough, doesn't scale ==<br />
<br />
There are really 2,099,999,997,690,000 (just over 2 quadrillion) maximum possible atomic units in the bitcoin design.<br />
<br />
The value of "1 BTC" represents 100,000,000 of these. In other words, each is divisible by up to 10^8. <br />
<br />
As the value of the unit of 1 BTC grows too large to be useful for day to day transactions, people can start dealing in smaller [[Units|units]], such as milli-bitcoins (mBTC) or micro-bitcoins (μBTC).<br />
<br />
== Bitcoins are stored in wallet files, just copy the wallet file to get more coins! ==<br />
<br />
No, your wallet contains your secret keys, giving you right to spend your bitcoins. Think of it like having bank details stored in a file. If you give your bank details (or bitcoin wallet) to someone else, that doesn't double the amount of money in your account. You can spend your money or they can spend your money, but not both.<br />
<br />
== Lost coins can't be replaced and this is bad ==<br />
<br />
Bitcoins are divisible to 0.00000001, so this is not a problem. If you lose your coins, all other coins will go up in value a little. Consider it a donation to all other bitcoin users.<br />
<br />
A related question is: Why don't we have a mechanism to replace lost coins? The answer is that it is impossible to distinguish between a 'lost' coin and one that is simply sitting unused in someone's safe.<br />
<br />
== It's a giant ponzi scheme ==<br />
In a Ponzi Scheme, the founders persuade investors that they’ll profit. Bitcoin does not make such a guarantee. There is no central entity, just individuals building an economy.<br />
<br />
Not to be confused with the [[Bitcoin randomizer|Bitcoin Randomizer]] which is a game that really is self-described as a Ponzi scheme.<br />
<br />
== Finite coins plus lost coins means deflationary spiral ==<br />
As deflationary forces may apply, economic factors such as hoarding are offset by human factors that may lessen the chances that a [[Deflationary spiral]] will occur.<br />
<br />
== Bitcoin can't work because there is no way to control inflation ==<br />
<br />
Inflation is simply a rise of prices over time, which is generally the result of the devaluing of a currency. This is a function of supply and demand. Given the fact that the supply of Bitcoins is fixed at a certain amount, unlike fiat money, the only way for inflation to get out of control is for demand to disappear.<br />
<br />
Given the fact that Bitcoin is a distributed system of currency, if demand were to decrease to almost nothing, the currency would be doomed anyway.<br />
<br />
The key point here is that Bitcoin as a currency can't be inflated by any single person or entity, like a government, as there's no way to increase supply past a certain amount.<br />
<br />
Indeed, the most likely scenario, as Bitcoin becomes more popular and demand increases, is for the currency to increase in value, or deflate, until demand stabilizes.<br />
<br />
== Bitcoin community are anarchist/conspiracy theorist/gold standard weenies ==<br />
<br />
CONFIRMED<br />
<br />
== Anyone with enough computing power can take over the network ==<br />
<br />
CONFIRMED, see [[Weaknesses]].<br />
<br />
That said, as the network grows, it becomes harder and harder for a single entity to do so. Already the bitcoin network's computing power is on par with some of the world's fastest supercomputers.<br />
<br />
What an attacker can do once the network is taken over is quite limited. Under no circumstances could an attacker take anybody else's money. An attacker's capabilities are limited to taking back their own money that they very recently spent, and preventing other people's transactions from receiving confirmations. Such an attack would be very costly in resources, and for such meager benefits there is little rational economic incentive to do such a thing.<br />
<br />
== Bitcoin violates some sort of government regulations ==<br />
<br />
Name them if you can.<br />
<br />
See also the [[Myths#Bitcoins_are_illegal_because_it_s_not_legal_tender|legal tender]] question.<br />
<br />
== Fractional reserve banking is not possible ==<br />
<br />
Yes, it is. <br />
<br />
1. Start Bitcoin Bank.<br />
<br />
2. Accept deposits from customers<br />
<br />
3. Make loans, using part of the funds deposited by customers, keeping a '''fraction''' thereof in '''reserve'''.<br />
<br />
4. Ask for your money to be returned, plus interest.<br />
<br />
5. PROFIT! <br />
<br />
See [http://en.wikipedia.org/wiki/Fractional-reserve_banking Fractional reserve banking].<br />
<br />
Peanut Gallery: But how does the bank guarantee that account holders can withdraw 100% of their bitcoins?<br />
<br />
Same way non-bitcoin banks do it - they don't. They rely on the government's [http://en.wikipedia.org/wiki/Federal_Deposit_Insurance_Corporation FDIC] program to insure depositors up to a certain amount (currently $250K USD per depositor). The FDIC is widely known to have reserves sufficient to cover only a very small fraction of the total deposits it insures.<br />
<br />
== Point of sale with bitcoins isn't possible because of the 10 minute wait for confirmation ==<br />
<br />
Tansactions '''can''' take tens of minutes to become confirmed, and this won't change for the forseeable future. Even after the computing power of the network is orders of magnitude larger than today, the difficulty of generating a block will self-adjust to maintain a target of 6 blocks per hour. Two potential solutions to allow POS transactions are:<br />
<br />
1) For small transactions, simply assume the customer isn't ripping you off. Give the customer his latte immediately after the transaction posts to the network. The transaction should propagate through the network almost instantly, allowing the seller to see the transaction within seconds (albeit with zero confirmations.) The cost of a double-spend attack should make small-scale fraud not worthwhile.<br />
<br />
2) Create a network of transaction hubs. These entities would communicate using a common API. They would float short-term loans between each other to facilitate instant transactions. <br />
<br />
Imagine that Alice uses Carol's Clearinghouse as her hub, and Bob uses Dave's Anonymous Exchange. Both Alice and Bob have accounts with their respective hubs, and have already deposited some Bitcoins in their accounts. When Alice wants to buy a latte from Bob at a point of sale, Alice tells Carol "I want to send Bob ''x'' Bitcoins. He uses Dave's Anonymous Exchange." After checking that Alice's account does contain at least ''x'' Bitcoins, Carol sends a message to Dave, saying "Credit Bob's account with ''x'' bitcoins immediately; I'll send you the real Bitcoins in the next block." Bob instantly sees his balance increase, and gives Alice her latte.<br />
<br />
As always, trust is required - Alice has to trust Carol, and the hubs have to trust each other. Due to competition, various hubs could develop with vastly different fee structures, membership requirements, trustability, etc.<br />
<br />
(But the point of bitcoin is you don't need trust to execute the transaction, in the above you replaced the bitcoins with a trust-based centralized authority.)<br />
<br />
== After 21 million coins are mined, no one will generate new blocks ==<br />
<br />
When operating costs can't be covered by the block creation bounty, which will happen some time before the total amount of BTC is reached, miners are expected to earn profit from [[transaction fees]].<br />
<br />
== Bitcoin has no built-in chargeback mechanism, and this is bad ==<br />
<br />
'''Why some people think this is bad''': Chargebacks are useful for limiting fraud. The person handling your money has a responsibility to prevent fraud. If you buy something on Ebay and the seller never ships it, PayPal takes funds from the seller's account and gives you back the money. This strengthens the Ebay economy, because people recognize that their risk is limited and are more willing to purchase items from risky sellers.<br />
<br />
'''Why it's actually a good thing''': Bitcoin is designed such that your money is yours and yours alone. Allowing chargebacks implies that it is possible for another entity to take your money from you. You can have either total ownership rights of your money, or fraud protection, but not both. <br />
<br />
The statement "The person handling your money has a responsibility to prevent fraud" is still true; the power has been shifted into your own hands. Fraud will always exist. It's up to you to only send bitcoins to trusted entities. It is possible to trust an online identity without ever knowing their physical identity; see the [http://wiki.bitcoin-otc.com/wiki/OTC_Rating_System OTC Web of Trust].<br />
<br />
== Bitcoin is just like all the other virtual currencies, nothing new ==<br />
<br />
All other virtual currencies are centrally controlled. This means that:<br />
* they can be printed at the subjective whims of the controllers<br />
* they can be destroyed by attacking the central point of control<br />
* arbitrary rules can be imposed upon their users by the controllers<br />
<br />
Being decentralized, bitcoin solves all of these problems.<br />
<br />
== Quantum computers would break bitcoin's security ==<br />
<br />
Yes, but quantum computers don't yet exist and probably won't for a while. Bitcoin's security can be [http://en.wikipedia.org/wiki/Post-quantum_cryptography upgraded] if this were considered an imminent threat.<br />
<br />
See the implications of quantum computers on public key cryptography here http://en.wikipedia.org/wiki/Quantum_computer#Potential<br />
<br />
The ''risk'' of quantum computers is also there for financial institutions, like banks, because they heavily rely on cryptography when doing transactions.<br />
<br />
== Bitcoin mining is a waste of energy and harmful for ecology ==<br />
<br />
No more so than the the wastefulness of mining gold out of the ground, melting it down and shaping it into bars, and then putting it back underground again. Not to mention the building of big fancy buildings, the waste of energy printing and minting all the various fiat currencies, the transportation thereof in armored cars by no less than two security guards for each who could probably be doing something more productive, etc. <br />
<br />
As far as mediums of exchange go, bitcoin is actually quite economical of resources, compared to others.<br />
<br />
== Shopkeepers can't seriously set prices in bitcoins because of the volatile exchange rate ==<br />
<br />
The assumption is that bitcoins must be sold immediately to cover operating expenses. This might not be the case for various reasons, make sure you need to do that.<br />
<br />
It's true that due to the small size of the bitcoin market, there's relatively high volatility. In the future volatility is expected to decrease, as the size and depth of the market grows. <br />
<br />
In the meantime, many merchants simply regularly pull the latest market rates from the exchanges and automatically update the prices on their websites. Also you might be able to buy a put option in order to sell at a fixed rate for a given amount of time. This would protect you from drops in price and simplify your operations for that time period.<br />
<br />
== Like Flooz and e-gold, bitcoins are great for criminals and so will be shut down ==<br />
<br />
* Hopefully bitcoin will grow to the point where no single organization can disrupt the network, or would be better served by helping it.<br />
* Terrorists fly aircrafts into buildings, but the governments have not yet abolished consumer air travel. Obviously the public good outweighs the possible bad in their opinion.<br />
* Criminal law differs between jurisdictions.<br />
<br />
== Bitcoins will be shut down by the government just like Liberty Dollars were ==<br />
<br />
Liberty Dollars consisted of a commercial venture to establish alternative US currency, including physical banknotes and coins, backed by precious metals. They were officially shut down for counterfeiting and intent to fraud. Bitcoins aren't commercial, physical, or backed by something. Different animals entirely.</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Category:History&diff=5785Category:History2011-03-22T19:25:34Z<p>Prcarter: </p>
<hr />
<div>* October 31, 2008<br />
** [http://article.gmane.org/gmane.comp.encryption.general/12588/ Bitcoin design paper] published<br />
* November 09, 2008<br />
** Bitcoin project registered at SourceForge.net<br />
* January 3, 2009<br />
** Genesis block established at 18:15:05 GMT<br />
* January 11, 2009<br />
** Bitcoin v0.1 released and announced on the [http://www.mail-archive.com/cryptography@metzdowd.com/msg10152.html cryptography mailing list]<br />
* December 16, 2009<br />
** Bitcoin v0.2 released<br />
* December 30, 2009<br />
** First difficulty increase at 06:11:04 GMT<br />
* February 6, 2010<br />
** [[Bitcoin Market]] established<br />
* May 22, 2010<br />
** lazslo first to buy pizza with Bitcoins [http://www.bitcoin.org/smf/index.php?topic=137.msg1195#msg1195 agreeing] upon paying 10,000btc for ~$25 worth of pizza courtesy of jercos<br />
* July 7, 2010<br />
** Bitcoin v0.3 released<br />
* July 11, 2010<br />
** Bitcoin v0.3 release [http://news.slashdot.org/story/10/07/11/1747245/Bitcoin-Releases-Version-03 mentioned on slashdot], bringing a large influx of new bitcoin users.<br />
* July 17, 2010<br />
** [[MtGox]] established<br />
* July 18, 2010<br />
** ArtForz generated his first block after establishing his personal OpenCL GPU hash farm<br />
* August 15, 2010<br />
** [[Incidents#Value_overflow|74638]]<br />
* September 14, 2010<br />
** jgarzik [http://www.bitcoin.org/smf/index.php?topic=133.msg12921#msg12921 offered] 10,000btc (valued at ~$600-650) to puddinpop to open source their windows-based CUDA client<br />
* September 18, 2010<br />
** puddinpop [http://www.bitcoin.org/smf/index.php?topic=133.msg13135#msg13135 released] source to their windows-based CUDA client under MIT license<br />
* September 29, 2010<br />
** kermit [http://www.bitcoin.org/smf/index.php?topic=1306.0 discovered] a microtransactions exploit which precipitated the Bitcoin v0.3.13 release<br />
* October 01, 2010<br />
** First public OpenCL miner released<br />
* October 04, 2010<br />
** Original Bitcoin History wiki page (this page) established (ooh so meta) on Bitcoin.org's wiki.<br />
* October 28, 2010<br />
** First bitcoin short sale transaction initiated, with a loan of 100 BTC by nanotube to [[User:Kiba|kiba]], facilitated by the [[Bitcoin-otc|#bitcoin-otc]] market.<br />
* November 6, 2010<br />
** The [http://www.bitcoin.org/smf/index.php?topic=1672 Bitcoin economy passed US $1 million]. The MtGox price touched USD $0.50.<br />
* December 7, 2010<br />
** Bitcoind was compiled for the Nokia N900 mobile computer by doublec. The following day, ribuck sent him 0.42 BTC in the first portable-to-portable Bitcoin transaction.<br />
* December 9, 2010<br />
** The generation difficulty passed 10,000.<br />
** First bitcoin call option contract sold, from nanotube to [[User:Sgornick|sgornick]], via the [[Bitcoin-otc|#bitcoin-otc]] market.<br />
* December 16, 2010<br />
** [http://mining.bitcoin.cz/ Bitcoin Pooled Mining], operated by slush, found its first block<br />
* January 2, 2011<br />
** [[Tonal BitCoin]] units standardized.<br />
* January 8, 2011<br />
** [[History of Bitcoin]] page (this page) created after replicating from original Bitcoin History page on Bitcoin.org.<br />
** Bitcoin Pooled Mining reached a total of 10,000 Mhash/s<br />
* January 27, 2011<br />
** Largest numeric value ever traded for bitcoins thus far occurred on this date. Three currency bills from Zimbabwe, known as Zimdollars, were traded on [[Bitcoin-otc|#bitcoin-otc]] at the rate of 4 BTC for each of the one-hundred trillion dollar ($100,000,000,000,000) Zimbabwe notes<ref>Serial numbers for Zimdollars sold: AA1669317, AA1669318 and AA1669319</ref><br />
* January 28, 2011<br />
** Block 105000 was generated. This means that 5.25 million bitcoins have been generated, which is just over one-quarter of the eventual total of nearly 21 million.<br />
* February 9, 2011<br />
** Decimal Bitcoin reached parity with the US dollar, touching $1 per BTC at [[MtGox]].<br />
* February 10, 2011<br />
** Bitcoin.org website struggles to handle [http://www.bitcoin.org/smf/index.php?topic=3444.0 traffic] resulting from mentions on Slashdot<ref>[http://news.slashdot.org/story/11/02/10/189246/Online-Only-Currency-BitCoin-Reaches-Dollar-Parity Online-Only Currency BitCoin Reaches Dollar Parity]</ref>, Hacker News and Twitter following the news that parity had been reached.<br />
* February 14, 2011<br />
** A vehicle was, for the first time, offered in exchange for a certain number of bitcoins<ref>[http://www.bitcoin.org/smf/index.php?topic=3485.0 Car for Sale - Australia]</ref>.<br />
* March 6, 2011<br />
** Total Bitcoin network computation speed for a short time [http://bitcoin.sipa.be/speed-lin.png reached an all-time high of almost 900Ghash/sec], dropping to 500Ghash/sec soon after. Some speculate that this was due to some supercomputer or bot-net that joined the network ("mystery miner").<br />
* March 18, 2011<br />
** BTC/USD exchange rate reaches a 6-week low point at almost $0.70/BTC, after what appeared to be a short burst of, possibly automated, BTC sales at progressively lower prices. BTC price had been declining since the February 9 high.<br />
<br />
{{fromold|bitcoin_history}}<br />
<br />
==References==<br />
<references /></div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Category:History&diff=5762Category:History2011-03-21T22:36:47Z<p>Prcarter: </p>
<hr />
<div>* October 31, 2008<br />
** [http://article.gmane.org/gmane.comp.encryption.general/12588/ Bitcoin design paper] published<br />
* November 09, 2008<br />
** Bitcoin project registered at SourceForge.net<br />
* January 3, 2009<br />
** Genesis block established at 18:15:05 GMT<br />
* January 11, 2009<br />
** Bitcoin v0.1 released and announced on the [http://www.mail-archive.com/cryptography@metzdowd.com/msg10152.html cryptography mailing list]<br />
* December 16, 2009<br />
** Bitcoin v0.2 released<br />
* December 30, 2009<br />
** First difficulty increase at 06:11:04 GMT<br />
* February 6, 2010<br />
** [[Bitcoin Market]] established<br />
* May 22, 2010<br />
** lazslo first to buy pizza with Bitcoins [http://www.bitcoin.org/smf/index.php?topic=137.msg1195#msg1195 agreeing] upon paying 10,000btc for ~$25 worth of pizza courtesy of jercos<br />
* July 7, 2010<br />
** Bitcoin v0.3 released<br />
* July 11, 2010<br />
** Bitcoin v0.3 release [http://news.slashdot.org/story/10/07/11/1747245/Bitcoin-Releases-Version-03 mentioned on slashdot], bringing a large influx of new bitcoin users.<br />
* July 17, 2010<br />
** [[MtGox]] established<br />
* July 18, 2010<br />
** ArtForz generated his first block after establishing his personal OpenCL GPU hash farm<br />
* August 15, 2010<br />
** [[Incidents#Value_overflow|74638]]<br />
* September 14, 2010<br />
** jgarzik [http://www.bitcoin.org/smf/index.php?topic=133.msg12921#msg12921 offered] 10,000btc (valued at ~$600-650) to puddinpop to open source their windows-based CUDA client<br />
* September 18, 2010<br />
** puddinpop [http://www.bitcoin.org/smf/index.php?topic=133.msg13135#msg13135 released] source to their windows-based CUDA client under MIT license<br />
* September 29, 2010<br />
** kermit [http://www.bitcoin.org/smf/index.php?topic=1306.0 discovered] a microtransactions exploit which precipitated the Bitcoin v0.3.13 release<br />
* October 01, 2010<br />
** First public OpenCL miner released<br />
* October 04, 2010<br />
** Original Bitcoin History wiki page (this page) established (ooh so meta) on Bitcoin.org's wiki.<br />
* October 28, 2010<br />
** First bitcoin short sale transaction initiated, with a loan of 100 BTC by nanotube to [[User:Kiba|kiba]], facilitated by the [[Bitcoin-otc|#bitcoin-otc]] market.<br />
* November 6, 2010<br />
** The [http://www.bitcoin.org/smf/index.php?topic=1672 Bitcoin economy passed US $1 million]. The MtGox price touched USD $0.50.<br />
* December 7, 2010<br />
** Bitcoind was compiled for the Nokia N900 mobile computer by doublec. The following day, ribuck sent him 0.42 BTC in the first portable-to-portable Bitcoin transaction.<br />
* December 9, 2010<br />
** The generation difficulty passed 10,000.<br />
** First bitcoin call option contract sold, from nanotube to [[User:Sgornick|sgornick]], via the [[Bitcoin-otc|#bitcoin-otc]] market.<br />
* December 16, 2010<br />
** [http://mining.bitcoin.cz/ Bitcoin Pooled Mining], operated by slush, found its first block<br />
* January 2, 2011<br />
** [[Tonal BitCoin]] units standardized.<br />
* January 8, 2011<br />
** [[History of Bitcoin]] page (this page) created after replicating from original Bitcoin History page on Bitcoin.org.<br />
** Bitcoin Pooled Mining reached a total of 10,000 Mhash/s<br />
* January 27, 2011<br />
** Largest numeric value ever traded for bitcoins thus far occurred on this date. Three currency bills from Zimbabwe, known as Zimdollars, were traded on [[Bitcoin-otc|#bitcoin-otc]] at the rate of 4 BTC for each of the one-hundred trillion dollar ($100,000,000,000,000) Zimbabwe notes<ref>Serial numbers for Zimdollars sold: AA1669317, AA1669318 and AA1669319</ref><br />
* January 28, 2011<br />
** Block 105000 was generated. This means that 5.25 million bitcoins have been generated, which is just over one-quarter of the eventual total of nearly 21 million.<br />
* February 9, 2011<br />
** Decimal Bitcoin reached parity with the US dollar, touching $1 per BTC at [[MtGox]].<br />
* February 10, 2011<br />
** Bitcoin.org website struggles to handle [http://www.bitcoin.org/smf/index.php?topic=3444.0 traffic] resulting from mentions on Slashdot<ref>[http://news.slashdot.org/story/11/02/10/189246/Online-Only-Currency-BitCoin-Reaches-Dollar-Parity Online-Only Currency BitCoin Reaches Dollar Parity]</ref>, Hacker News and Twitter following the news that parity had been reached.<br />
* February 14, 2011<br />
** A vehicle was, for the first time, offered in exchange for a certain number of bitcoins<ref>[http://www.bitcoin.org/smf/index.php?topic=3485.0 Car for Sale - Australia]</ref>.<br />
* March 6, 2011<br />
** Total Bitcoin network computation speed for a short time [http://bitcoin.sipa.be/speed-lin.png reached an all-time high of almost 900Ghash/sec], dropping to 500Ghash/sec soon after. Some speculate that this was due to some supercomputer or bot-net that joined the network.<br />
* March 18, 2011<br />
** BTC/USD exchange rate reaches a 6-week low point at almost $0.70/BTC, after what appeared to be a short burst of, possibly automated, BTC sales at progressively lower prices. BTC price had been declining since the February 9 high.<br />
<br />
{{fromold|bitcoin_history}}<br />
<br />
==References==<br />
<references /></div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=User_talk:Prcarter&diff=5761User talk:Prcarter2011-03-21T22:18:46Z<p>Prcarter: </p>
<hr />
<div>Your change to [[Mining hardware comparison]] at 07:02, 4 March 2011, claimed 300 MH/s on a Radeon 5850 with poclbm. How did you get that? --[[User:Luke-jr|Luke-jr]] 05:03, 15 March 2011 (GMT)<br />
:I was just copying from [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 this post]. For the wattages I read from the manufacturer's websites. --[[User:Prcarter|Prcarter]] 22:16, 21 March 2011 (GMT)<br />
:It must have been overclocked I guess. --[[User:Prcarter|Prcarter]] 22:18, 21 March 2011 (GMT)</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=User_talk:Prcarter&diff=5760User talk:Prcarter2011-03-21T22:16:52Z<p>Prcarter: </p>
<hr />
<div>Your change to [[Mining hardware comparison]] at 07:02, 4 March 2011, claimed 300 MH/s on a Radeon 5850 with poclbm. How did you get that? --[[User:Luke-jr|Luke-jr]] 05:03, 15 March 2011 (GMT)<br />
:I was just copying from [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 this post]. For the wattages I read from the manufacturer's websites. --[[User:Prcarter|Prcarter]] 22:16, 21 March 2011 (GMT)</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4887Mining hardware comparison2011-03-04T11:37:19Z<p>Prcarter: /* Intel */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 57.83 || 0.294 || 197 || || 2x128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 28 || 0.142 || 197 || || 2x128 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Celeron E330 || 2/2 || 2.2 || 0.03 || 65W || 2.5 GHz || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|-<br />
| Core i5 ? || 4/? || 6.5 || || || || client from svn || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37621#msg37621 source]<br />
|-<br />
| Core i7 980x || 6/12 || 19.2 || 0.15 || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4886Mining hardware comparison2011-03-04T11:36:22Z<p>Prcarter: human error...</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 57.83 || 0.294 || 197 || || 2x128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 28 || 0.142 || 197 || || 2x128 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Celeron E330 || 2/2 || 2.2 || 0.03 || 65W || 2.5 GHz || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|-<br />
| Core i5 ? || 4/? || 6.5 || || || || client from svn || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37621#msg37621 source]<br />
|-<br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4884Mining hardware comparison2011-03-04T10:09:34Z<p>Prcarter: /* Intel */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 57.83 || 0.294 || 197 || || 2x128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 28 || 0.142 || 197 || || 2x128 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Celeron E330 || 2/2 || 2.2 || 0.34 || 65W || 2.5 GHz || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|-<br />
| Core i5 ? || 4/? || 6.5 || || || || client from svn || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37621#msg37621 source]<br />
|-<br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4883Mining hardware comparison2011-03-04T10:07:20Z<p>Prcarter: /* Nvidia */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 57.83 || 0.294 || 197 || || 2x128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 28 || 0.142 || 197 || || 2x128 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Celeron E330 || 2/2 || 2.2 || 0.34 || 65W || 2.5 GHz || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4882Mining hardware comparison2011-03-04T10:06:21Z<p>Prcarter: /* Nvidia */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 57.83 || 0.294 || 197 || || 2x128 ||<br />
|-<br />
|style="background-color:#FFEFEF"| 9800GX2 || 28 || 0.142 || 197 || || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Celeron E330 || 2/2 || 2.2 || 0.34 || 65W || 2.5 GHz || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4879Mining hardware comparison2011-03-04T10:00:09Z<p>Prcarter: /* Intel */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Celeron E330 || 2/2 || 2.2 || 0.34 || 65W || 2.5 GHz || 0.3.19/Ubuntu10.04 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37620#msg37620 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4878Mining hardware comparison2011-03-04T09:55:32Z<p>Prcarter: /* Nvidia */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || || || || 32 ||<br />
|-<br />
| 8600GT || 5.66 || || || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || 0.24 || 105 || 1300 || ||<br />
|-<br />
| 8800GT || 24.5 || 0.23 || 105 || 1300 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || || || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || || || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || || || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4877Mining hardware comparison2011-03-04T09:50:20Z<p>Prcarter: /* AMD */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 4400+ || || 2.09 || 0.32 || 65W || 2.3GHz || 0.3.19/Win x64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source]<br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon XP 2000+ || 2 || 0.62 || 0.009 || 70W || 1.67 GHz || 0.3.18/Ubuntu || [http://www.bitcoin.org/smf/index.php?topic=1628.msg37592#msg37592 source] [http://www.pcstats.com/articleview.cfm?articleid=914&page=4 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4876Mining hardware comparison2011-03-04T09:37:22Z<p>Prcarter: /* Intel */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4875Mining hardware comparison2011-03-04T09:33:48Z<p>Prcarter: bitcoind was mentioned</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4874Mining hardware comparison2011-03-04T09:24:03Z<p>Prcarter: /* AMD */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4873Mining hardware comparison2011-03-04T09:20:22Z<p>Prcarter: /* AMD */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 250.26 || 1.657 || 151 || || || || opencl client || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4872Mining hardware comparison2011-03-04T09:12:58Z<p>Prcarter: /* Intel */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || 2.2 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || 2.1 || poclbm/Linux || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5630 (dual) || 2x4/8 || 8 || 0.1 || 80W || 2.53 GHz || 0.3.17 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg29471#msg29471 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4871Mining hardware comparison2011-03-04T09:06:39Z<p>Prcarter: /* Nvidia */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || 2.2 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || 2.1 || poclbm/Linux || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX460 (2 cards) || 102 || 0.319? || 320? || 1350 || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4869Mining hardware comparison2011-03-04T08:26:09Z<p>Prcarter: /* AMD */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || 2.2 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900? || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900? || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900? || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 340 || 1.809 || 188 || 850 || 1600 || 2.1 || poclbm/Linux || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26363#msg26363 source]<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4868Mining hardware comparison2011-03-04T08:18:29Z<p>Prcarter: </p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || 2.2 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900 || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900 || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900 || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 || 2/2 || 7.76 || 0.11 || 70W || 3.33 GHz (o/c?) || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarterhttps://tests.bitcoin.it/w/index.php?title=Mining_hardware_comparison&diff=4867Mining hardware comparison2011-03-04T08:12:40Z<p>Prcarter: /* Intel */</p>
<hr />
<div>{{stub}}<br />
<br />
Below are some statistics about the mining performance of various hardware used in a [[mining rig]]. The GPU lists were originally compiled by ArtForz.<br />
<br />
The table shows stock clock numbers. 10-20% performance improvement can be achieved via overclocking.<br />
<br />
=Graphics cards=<br />
<br />
==AMD==<br />
To get the maximum performance use the 2.1 or 2.2 release of the ATI Stream SDK. 2.3 performance drops by 5-10%.<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner !! Notes<br />
|-<br />
| 3XXX || || || || || || || || OpenCL Not Supported<br />
|-<br />
| 4350 || 6.93 || 0.346 || 20 || 575 || 80 || || poclbm || -w 32, don't use vectors <br />
|-<br />
| 4550 || 7.23 || 0.289 || 25 || 600 || 80 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4650 || 31.33 || 0.653 || 48 || 650 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4670 || 36.14 || 0.613 || 59 || 750 || 320 || || poclbm || -w 32, don't use vectors <br />
|- <br />
| 4730 || 72.29 || 0.657 || 110 || 750 || 640 || || ||<br />
|- <br />
| 4770 || 72.29 || 0.904 || 80 || 750 || 640 || || ||<br />
|- <br />
| 4830 || 55.42 || 0.583 || 95 || 575 || 640 || || ||<br />
|-<br />
| 4850 || 75.30 || 0.685 || 110 || 625 || 800 || || ||<br />
|- <br />
| 4860 || 67.47 || 0.519 || 130 || 700 || 640 || || ||<br />
|-<br />
| 4870 || 90.36 || 0.602 || 150 || 750 || 800 || 2.1 || clmine ||<br />
|-<br />
| 4870 || 78 || || || || || || m0mchil's OpenCL/Vista 64bit || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source]<br />
|- <br />
| 4890 || 102.41 || 0.539 || 190 || 850 || 800 || || ||<br />
|- <br />
| 4850X2 || 150.60 || 0.602 || 250 || 625 || 1600 || || ||<br />
|- <br />
| 4870X2 || 180.72 || 0.632 || 286 || 750 || 1600 || || ||<br />
|- <br />
| 5450 || 11.99 || 0.631 || 19 || 650 || 80 || || ||<br />
|- <br />
| 5550 || 40.59 || 1.041 || 39 || 550 || 320 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 59.96 || 1.538 || 39 || 650 || 400 || || ||<br />
|- <br />
|style="background:#FFFFEF;"| 5570 || 64 || 1.641 || 39 || 650 || || || m0mchil's OpenCL/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
| 5650 || 48 || 2.5-3.2 ? || 15-19 ? || || || || m0mchil's OpenCL/Win7-64 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source] [http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-5650.23697.0.html source]<br />
|- <br />
| 5670 || 71.49 || 1.117 || 64 || 775 || 400 || || ||<br />
|- <br />
| 5750 || 116.24 || 1.352 || 86 || 700 || 720 || || ||<br />
|- <br />
| 5770 || 156.83 || 1.452 || 108 || 850 || 800 || 2.1 || clmine ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 206.64 || 1.181 || 175 || 800 || 1120 || || ||<br />
|- <br />
|style="background:#FFFFFF;"| 5830 || 241 || 1.377 || 175 || 1006 || || 2.3 || poclbm 2011-02-04 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 240.77 || 1.595 || 151 || 725 || 1440 || || ||<br />
|-<br />
|style="background:#EFEFFF;"| 5850 || 252 || 1.669 || 151 || 765 || || 2.3 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 255.3 || 1.690 || 151 || 765 || || 2.2 || poclbm 2011-01-25 ||<br />
|- <br />
|style="background:#EFEFFF;"| 5850 || 300 || 1.987 || 151 || || || 2.2 || m0mchil's OpenCL || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313.65 || 1.668 || 188 || 850 || 1600 || 2.1 || clmine ||<br />
|- <br />
|style="background:#EFFFEF;"| 5870 || 313 || 1.665 || 188 || 900 || 1600 || 2.3 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 343 || 1.824 || 188 || 900 || 1600 || 2.1 || Diablo/Linux ||<br />
|-<br />
|style="background:#EFFFEF;"| 5870 || 355 || 1.888 || 188 || 900 || 1600 || 2.1 || poclbm/Linux ||<br />
|- <br />
|style="background:#FFEFEF;"| 5970 || 535.06 || 1.820 || 294 || 725 || 3200 || 2.1 || clmine ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 560 || 1.905 || 294 || 725 || || || Diablo ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 565 || 1.922 || 294 || || || 2.1 || clmine2 ||<br />
|-<br />
|style="background:#FFEFEF;"| 5970 || 604 || 2.054 || 294 || || || 2.1 || clmine ||<br />
|- <br />
| 6850 || 171.59 || 1.351 || 127 || 775 || 960 || 2.1 || clmine ||<br />
|- <br />
| 6870 || 232.47 || 1.540 || 151 || 900 || 1120 || || ||<br />
|- <br />
| 6970 || 323 || 1.468 || 220 || 880 || 1536 || 2.3 || poclbm || -w 64<br />
|- <br />
|}<br />
<br />
==Intel==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! SDK !! Miner<br />
|-<br />
| HD 2000 || 0.65 || || || || || 2.2 || poclbm 2011-01-25<br />
|- <br />
|}<br />
<br />
==Nvidia==<br />
<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! Mhash/s !! Mhash/W !! W !! Clock !! SP !! Comment<br />
|-<br />
| 8600M GT || 4.93 || - || - || - || 32 ||<br />
|-<br />
| 8600GT || 5.66 || - || - || 1188 || 32 ||<br />
|-<br />
| 8800GT || 25 || - || - || 1300 || 112 ||<br />
|-<br />
| 8800GTS || 16.8 || 0.05 || 291 ? || || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg25069#msg25069 source] [http://www.techspot.com/review/79-geforce-8800-gts-512/page11.html source]<br />
|-<br />
| 9300GE || 1.57 || - || - || 1300 || 8 ||<br />
|-<br />
| 9300GS || 1.69 || - || - || 1400 || 8 ||<br />
|-<br />
| 9400GT || 3.37 || 0.067 || 50 || 1400 || 16 ||<br />
|-<br />
| 9500GT || 6.75 || 0.135 || 50 || 1400 || 32 ||<br />
|-<br />
| 9600GSO || 19.88 || 0.237 || 84 || 1375 || 96 ||<br />
|-<br />
| 9600GSO512 || 11.75 || 0.131 || 90 || 1625 || 48 ||<br />
|-<br />
| 9600GT || 15.66 || 0.165 || 95 || 1625 || 64 ||<br />
|-<br />
| 9800GT || 30.36 || 0.289 || 105 || 1800 || 112 ||<br />
|-<br />
| 9800GTX || 32.54 || 0.232 || 140 || 1688 || 128 ||<br />
|-<br />
| 9800GTX+ || 35.39 || 0.251 || 141 || 1836 || 128 ||<br />
|-<br />
| 9800GX2 || 57.83 || 0.294 || 197 || 1500 || 2x128 ||<br />
|-<br />
| G210 || 3.38 || 0.111 || 30.5 || 1402 || 16 ||<br />
|-<br />
| GT220 || 9.83 || 0.170 || 58 || 1360 || 48 ||<br />
|-<br />
| GT240 || 19.37 || 0.281 || 69 || 1340 || 96 ||<br />
|-<br />
| GTS250 || 35.39 || 0.244 || 145 || 1836 || 128 ||<br />
|-<br />
| GTX260 || 35.91 || 0.178 || 202 || 1242 || 192 ||<br />
|-<br />
| GTX260 || 44 || 0.242 || 182 || 1242 || 216 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| GTX260c216 || 40.40 || 0.236 || 171 || 1242 || 216 ||<br />
|-<br />
| GTX275 || 50.75 || 0.232 || 219 || 1404 || 240 ||<br />
|-<br />
| GTX280 || 46.84 || 0.198 || 236 || 1296 || 240 ||<br />
|-<br />
| GTX285 || 53.35 || 0.262 || 204 || 1476 || 240 ||<br />
|-<br />
| GTX295 || 89.78 || 0.311 || 289 || 1242 || 480 ||<br />
|-<br />
| 320M (MacBook Air) || 6.12 || - || - || 1212 || 48 ||<br />
|-<br />
| GT430 || 20.24 || 0.413 || 49 || 1400 || 96 ||<br />
|-<br />
| GTS450 || 45.28 || 0.427 || 106 || 1566 || 192 ||<br />
|-<br />
| GTX460SE || 56.39 || 0.376 || 150 || 1300 || 288 ||<br />
|-<br />
| GTX460 || 68.31 || 0.427 || 160 || 1350 || 336 ||<br />
|-<br />
| GTX465 || 64.41 || 0.322 || 200 || 1215 || 352 ||<br />
|-<br />
| GTX470 || 81.98 || 0.381 || 215 || 1215 || 448 ||<br />
|-<br />
| GTX480 || 101.28 || 0.405 || 250 || 1401 || 480 ||<br />
|-<br />
| GTX570 || 105.83 || 0.483 || 219 || 1464 || 480 ||<br />
|-<br />
| GTX580 || 119.06 || 0.488 || 244 || 1544 || 512 ||<br />
|-<br />
|}<br />
<br />
=CPUs=<br />
<br />
A lot of nice data can be pulled from [http://www.bitcoin.org/smf/index.php?topic=1628.0 this thread] to seed this section. Also from [https://www.bitcoin.org/wiki/doku.php?id=bitcoin_miners this page on the old wiki].<br />
<br />
==AMD==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! nprocs !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| 2x Opteron 6128 || 16 || 32.4 || 0.203 || 160W || 2 GHz || 0.3.19 || -4way<br />
|-<br />
| Athlon X2 4000+ || 2 || 1.9 || 0.02 || 65W || 2.1 GHz || rpc-miner || <br />
|-<br />
| Athlon X2 6000+ || 2 || 2.81 || 0.02 || 125W || 3 GHz || || [http://www.bitcoin.org/smf/index.php?topic=1628.msg22881#msg22881 source]<br />
|-<br />
| Athlon II X2 240e || 2 || 2.71 || 0.06 || 45W || 2.81 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1055T || 6 || 15.84 || 0.13 || 125W || 2.82 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Phenom II X6 1100T || 6 || 22 || 0.176 || 125W || 3.82 GHz || bitcoin-miner || Aciid#bitcoin-dev<br />
|-<br />
| Phenom II X3 720 || 3 || 3.8 || 0.04 || 95W || 2.8 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|-<br />
| Phenom II X3 720 || 3 || 7.2 || 0.08 || 95W || 2.8 GHz || cpu-miner 0.2.1/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
==Intel==<br />
{| class="wikitable sortable"<br />
|-<br />
! Model !! p/t !! Mhash/s !! Mhash/W !! ACP [W] !! Clock !! Version !! Comment<br />
|-<br />
| Core i3 M350 || 2/4 || 1.48 || 0.04 || 35W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|- <br />
| Core i5 M450 || 2/4 || 1.8 || 0.05 || 35W || 1.2 GHz || 0.3.17/Win7-54 || [http://www.bitcoin.org/smf/index.php?topic=1628.msg26292#msg26292 source]<br />
|-<br />
| Core i5-2400 || 4/4 || 4.5 || 0.05 || 95W || 3.1 GHz || cpuminer git (2011-01-22) || cryptopp_asm32<br />
|- <br />
| Core i5-550 ? || 2/4 || 5.1 || 0.04 ? || || 3.2 GHz || cpuminer-0.7 || -4way<br />
|- <br />
| Core i7 980x || 6/12 || 19.2 || '''0.15''' || 130 || 4.4 GHz (x33) || cpuminer/Win7-64 || <br />
|- <br />
| Core i7 980x || 6/12 || 8.7 || || || 3.9 GHz (x27) || 0.3.17/Win7-64 || <br />
|- <br />
| Core 2 Duo E7300 ? || 2/2 || 7.76 ? || 0.11 ? || 70W || 3.33 GHz ? || ufasoft-0.3 || miner optimized for Intel Core<br />
|-<br />
| Core 2 Duo E7300 || 2/2 || 2.52 || 0.04 || 65W || 2.66 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Pentium Dual-Core E5400 || 2/2 || 2.27 || 0.03 || 65W || 2.7 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5520 || 4/8 || 6.5 || 0.08 || 80W || 2.27 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Xeon E5530 || 4/8 || 7.14 || 0.09 || 80W || 2.4 GHz || bitcoind || [http://www.bitcoin.org/smf/index.php?topic=1628.msg19426#msg19426 source]<br />
|-<br />
| Pentium III mobile ? || 1 || 0.3 || 0.014 || 21W || 1.07 GHz || 0.3.1x/Win2K || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source] [http://ark.intel.com/Product.aspx?id=27380 source]<br />
|-<br />
| Atom N270 || 1 || 0.42 || '''0.17''' || 2.5W || 1.6 GHz || 0.3.1x/WinXP || [http://www.bitcoin.org/smf/index.php?topic=1628.msg24699#msg24699 source]<br />
|}<br />
<br />
[[Category:Mining]]</div>Prcarter