No problem, and you've got it. Either the S3 or the S7 can find a block at any time. Statistically, the S7 will find a block in 10x less time than the S3.
If you're using the lottery analogy, your S3 checks 440,000,000,000 times a second to see if it's found a winner. The S7 checks 4,750,000,000,000 times a second. When talking about pools and "shares", we are referring to a baseline called a "difficulty 1 share". We use the large numbers because it's frankly easier for the human mind to comprehend something being more "difficult" if it's perceived as a large number. The reality is that the share is actually a very small number (lots of leading zeroes).
At any rate, you can use math to figure out how long you would expect it to take to find that baseline share (diff 1). The formula for doing so can be simplified to:
Applying that formula, you can easily calculate that your S7 expects to find a diff 1 share every 0.00090420364126 seconds. Inverting that gives you how many diff 1 shares per second your S7 should find: 1105.94555735974321.
Now that you have this, and you know the current network difficulty, you can figure out the expected time to solve a block:
Again, using the S7 as an example, at the current difficulty, you would expect to find a block after hashing for 161561576.41029279010546 seconds. Convert that into days and you'll see an S7 would expect to take 1869.92565289690729 days to find a block.
Given this information, you can then figure out what your expected daily earnings are for an S7 because you know the current block reward is 25BTC. Simply take 25 and divide it by the number of days to solve a block and you'll get 0.01336952BTC a day.
Putting all that together into a single formula:
If you want the more advanced version of that formula (one that doesn't approximate a diff 1 share to 2^32), here it is:
If you're using the lottery analogy, your S3 checks 440,000,000,000 times a second to see if it's found a winner. The S7 checks 4,750,000,000,000 times a second. When talking about pools and "shares", we are referring to a baseline called a "difficulty 1 share". We use the large numbers because it's frankly easier for the human mind to comprehend something being more "difficult" if it's perceived as a large number. The reality is that the share is actually a very small number (lots of leading zeroes).
At any rate, you can use math to figure out how long you would expect it to take to find that baseline share (diff 1). The formula for doing so can be simplified to:
Code:
2^32 / hashrate = time to find a diff 1 share
Applying that formula, you can easily calculate that your S7 expects to find a diff 1 share every 0.00090420364126 seconds. Inverting that gives you how many diff 1 shares per second your S7 should find: 1105.94555735974321.
Now that you have this, and you know the current network difficulty, you can figure out the expected time to solve a block:
Code:
current diff / shares per second = time in seconds to find a block
Again, using the S7 as an example, at the current difficulty, you would expect to find a block after hashing for 161561576.41029279010546 seconds. Convert that into days and you'll see an S7 would expect to take 1869.92565289690729 days to find a block.
Given this information, you can then figure out what your expected daily earnings are for an S7 because you know the current block reward is 25BTC. Simply take 25 and divide it by the number of days to solve a block and you'll get 0.01336952BTC a day.
Putting all that together into a single formula:
Code:
25 / (current diff * 2^32 / hashrate / 86400) = expected earnings per day
If you want the more advanced version of that formula (one that doesn't approximate a diff 1 share to 2^32), here it is:
Code:
(reward / (2^256 / (((2^224 - 2^208) / difficulty) * hashrate))) * 86400 = expected earnings per day
This is the most concise, informative post I've read on the subject. Maybe you wouldn't mind explaining to me how the stratum protocol works. When I mine on a pool that uses stratum does my miner receive the same exact work as all other miners?
All miners receive the same work, produce a hash and then increment a random number called the nonce in an attempt to get a share above network difficulty, which solves the block. Is that correct?
Also, congrats on your extraordinary luck lately.