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55

Sure: 1 kH/s is 1,000 hashes per second (sometimes mistakenly written KH/s). 1 MH/s is 1,000,000 hashes per second. 1 GH/s is 1,000,000,000 hashes per second. 1 TH/s is 1,000,000,000,000 hashes per second. 1 PH/s is 1,000,000,000,000,000 hashes per second.


32

Mining capability is measured in the number of attempts to find a block a miner can perform. Each attempt consists of creating a unique block candidate, and creating a digest of the block candidate by means of the SHA-256d, a cryptographic hashing function. Or, in short, a hash. Since this is a continuous effort, we speak of hashes per second or [H/s]. Hash ...


30

Basically the idea is that you assemble a Namecoin block and hash it, and then insert that hash into a Bitcoin block. Now when you solve the Bitcoin block at a difficulty level greater to or equal to the Namecoin difficulty level, it will be proof that that amount of work has been done for the Namecoin block. The Namecoin protocol has been altered to ...


21

The user C121 on r/bitcoin explored this topic in the thread Mining Bitcoin by hand. He states that it takes 3385 integer operations to calculate one double SHA-256 hash. His conclusion was that you would reach about 0.00003 H/s, or in other terms, it would take about 9.4 hours for one hash, assuming the human in question could do a 32-bit operation in 10 ...


18

Check this page: How soon might I expect to generate a block? So with the current difficulty 510,929,738, and a 1Ghash/s mining rig (faster than your CPU) you'd do this math: 510929738 * Math.pow(2,32) / Math.pow(10,9) / 60 / 60 / 24 / 365 So to find a block at this difficulty with a 1Ghash mining rig it would take you about 69 years on average. Good ...


17

Take the total network Th/s and divide by your total Th/s. That number gives you you a number that tells you how many blocks will occur before you get one (on average). So if there is currently 3,666 Th/s on the network, and you have a 0.55 Th/s (like you would if you have a $5,000 KNCMiner Jupiter ASIC), then 3,666/0.55 = 6,665. That means you have 1/6,...


15

There are too many issues rolled up into this question, I'll try to address each separately. The fact that the miner does not include transactions is not a problem. Miners have a right to exclude transactions, even all transactions. Senders can include tx fees if they want to improve the chances of being included quickly (if the miner excludes transactions ...


15

(If I may repeat myself a bit...) Mining is like having a lot of people throwing weighted coins (such that 1 millionth of the time it comes up heads) and telling you when they hit a heads. If one such "heads" is reported every 10 minutes (600 seconds), you can make a very accurate estimation of how many times per second the coins are being flipped. In this ...


13

As long as you're in good communication with the network and have a hashrate measured in something better than minutes per hash, yes, you technically do have a chance of successfully mining a block, even if your hashrate is tiny compared to the whole network. Then the question is, what are your chances and should you do it? I think an analogy with a lottery ...


13

Mining is not won by the miner with the "strongest ability to solve the block". Mining is a random process, not a linear stack of work that needs to be powered through. This is because each miner works on different inputs to their block: As everyone is trying to send the block reward to themselves, they are using different Coinbase transactions. Therefore, ...


12

The size of a pool, its total hashrate and the distribution of hashrate between bigger and smaller miners, have no effect on the rewards you, mining with a specific hashrate, will obtain on average. The total block rewards collected by the pool are proportional to the number of blocks it finds per time unit, which is proportional on average to its total ...


11

Network hashrate calculated using formula: H ~= h / t , where t is time that took to find X number of blocks and h is approximate number of hashes it should have taken to solve X number of blocks, h = X * (D * 2**256 / (0xffff * 2**208)) Wiki:Difficulty Bitcoin network hashrate stats available at bitcoinwatch.com and bitcoincharts.com .


10

A supercomputer is way slower than mining with ASICs. A supercomputer only has much CPU power, not even GPU power and ASICs are way more powerfull than GPUs. ASICs represent the hashing algorithm as hardware which means they can't do anything else, that's why they are so fast. At http://bitcoinwatch.com/ you can see the current network hashrate in PetaFLOPS,...


10

Mining is a self-adjusting system. The difficulty only rises in accordance to the available mining power. Hence, it can neither go to a difficulty where it will take months for a block to be found, nor can it become prohibitely expensive to mine. Also see How is difficulty calculated?.


9

These charts show the approximate network hash rate on the left axis: http://bitcoin.sipa.be/ We know the network adjusts for 25 new bitcoins per 10 minutes. Together this provides enough info to give an approximate answer to your question: hashes per bitcoin = (network hash rate) / (25 BTC per 10 minutes) = (180 * Th / s) / (25 * BTC / (600 * s) ) = ...


8

The variability is exactly the same no matter the difficulty. It is always an exponentially distributed random variable with mean 10 minutes (the mean could be slightly off if hashrate mismatches difficulty). What we may see in the future however is a reduction in variance due to decrease of the block reward. As transaction fees become a more significant ...


8

Well, currently the difficulty is 2,440,643. There will be (difficulty * 2^32) (roughly) hashes per block. So that means there are (2,440,643 * 2^32) hashes that must occur before one block is solved. That's is across the entire network. A block is solved in ten minutes (on average) or 600 seconds. So the network is hashing (2,440,643 * 2^32) / 600 ~= ...


8

Blockchain.info reckons the network used 156.51 megawatt hours of electricity in the last 24 hours. This random physics page I googled up reckons a car driving at 40mph takes 100kW (so, 2.4 MWh in 24 hours). So by these (very) rough figures, running the Bitcoin network takes about as much energy as driving 65 cars. How many vehicles are used in the ...


8

I think you misunderstand the problem. The reason mining is becoming impractical is because there's too much of it. It's like a restaurant that's too crowded. It means you can't get a table, but the restaurant is not going to go out of business.


8

I do not think the question was about the "how long" it would take in average, but what are the odds, which is something completely different from my point o view. If I understand well the concept of solving blocks then there are always more people/groups/pools trying to solve one block. If that's so then solving a block is always more about the luck than ...


8

This is a valid concern and I think nobody can give you a clear answer here. We'll just have to wait how it evolves and how people react; it is an unclear future. There are some ideas about changing the proof-of-work algorithm to make mining pools not that profitable, but the effects of such implementations could be various. I highly recommend this article ...


8

Laptop mining worked well in 2009. It is no longer 2009. Your integrated Intel GPU has the speed of a CPU, not a fast gaming GPU. Even in 2011 when CPU mining was dying and people mined on GPUs your GPU would be too slow. Yes, "even" people with 100 MH/s can't mine anymore. That's because 1000x that speed (100 GH/s) is slow at this point. 1 TH/s (1 000 000 ...


7

If the average time to find a block is T, and the typical time for a found block to propagate in the network is t, then the proportion of orphans among all blocks will be roughly 1/(1+T/t). As long as T>t there's not much risk for the network; however it could be a challenge for orphan-paying pools, for example If T=9t then 10% of the block rewards will need ...


7

A short term increase in the gradient on the graph can be caused by a large and fast relative increase in hashing speed of the total network. Within a short time, the difficulty adjusts and prevents it having a substantial long term impact. The steep gradient on this difficulty graph between 13GH/s and around 20GH/s is an increase of around 50% in hashpower ...


7

If the current difficulty is D, then the target hash (the value below which block hashes must go) is: 0x00000000FFFF0000000000000000000000000000000000000000000000000000 / D (by definition of difficulty, which is a fraction of the maximum target), or otherwise put, the number of valid hashes is: 65535 * 2208 / D Which means that the ratio of all ...


7

Miners task is to find a hash below a target T. Obviously if T is smaller, its more difficult to find the hash number. Difficulty D is defined by: D = Tmax/T where Tmax is: 2^224 The probability of finding the hash is: P = T/2^256 which is equal to 1/D2^32 So if you can make h number of hashes in t time, the probability of finding the target hash is: P =...


7

Divide this number by the number of seconds in a day (86400) to get the required number of hashes per second to solve one block per day on average. You might get more than one block on some days and no blocks on others. It's random. Currently, you'd need about 931 TH/s, which is a ridiculous amount of mining power.


7

Let's try to make a rough estimate. Intel's article Intel SHA Extensions gives some details on these instructions as well as sample code. The main feature is the sha256rnds2 instruction, which performs two rounds of SHA256, out of the 64 rounds that are needed to hash one 64-byte block. A Bitcoin header is 80 bytes long, so that's 2 blocks, and because ...


6

Satoshi himself seems to be the inventor of merged mining. In his words (bitcointalk.org): I think it would be possible for BitDNS to be a completely separate network and separate block chain, yet share CPU power with Bitcoin. The only overlap is to make it so miners can search for proof-of-work for both networks simultaneously. The networks wouldn'...


6

From Wiki:Mining hardware comparison: Core 2 Quad Q9650 - 18.67 Mhash/s . With current price and difficulty factor there is no point in using CPU for mining because the profit won't cover the cost of hardware or electricity. For example with current difficulty it will take you 8 years on average to uncover block and earn 50 BTC or 1/2 BTC a month if mining ...


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