Quote from: QuintLeo on December 26, 2017, 10:29:43 PM

Quote from: mikez_nj on December 26, 2017, 02:01:14 PM

Quote from: Didley1JT on December 26, 2017, 04:39:04 AM

Quote from: mikez_nj on December 26, 2017, 03:35:54 AM

Quote from: timk225 on December 26, 2017, 03:12:47 AM

I've done a cost / benefit analysis on the 821 and 841, and they are both far better than the 741 for power usage and hash rate.

How can one do a "cost / benefit analysis" without knowing the cost? Asking for a friend.

I think he just calculated that (7.3TH/s divided by 1150 Watts) is less than (11TH/s divided by 1200 Watts). But yeah... obviously.

If anyone is willing to pay the price for the 821 (they will), then it doesn't matter what the actual ROI is... the fact that a more efficient machine is mining the same currencies immediately reduces your earnings. This is why you can't just decide to fill a warehouse with Avalon 6s to avoid buying Avalon 8s.

It's not the efficiency that matters, it's the overall hashrate being added to the pool (and the timing of it being added) that affects earnings. Network difficulty is what drives earnings, and network difficulty is a function of network hashrate.

Efficiency affects NET earnings quite a bit, unless you have free power available in a capacity greater than you can afford to buy miners to fill up.

Difficulty affects net AND gross earnings as well - specifically as it is a function of *time* and hashrate. It's very possible for one machine to be much less efficient and still be more profitable than another machine simply because it is available sooner. Profitability calculators are mostly bullshit for a number of reasons, not the least of which is they don't accurately model difficulty over time very well.