Except that it's not. The time to recover the cost of the card on the same Equihash coin is 61 days for a $750 1080 Ti that produces 750 H/s vs 41 days for a $200 RX 470 4 GB card that produces 300 H/s on Equihash.
Might have been true a month ago, but try finding ANY RX 470/480/570/580 for less than $500 or so TODAY.
If you can find them at all.
Per all the reports I've seen, the odds are looking good that the current "shortage" and resulting gouge pricing may last MONTHS on AMD RX 570/580 cards (and the 470/480 is out of production of course).
To be fair though, $200 a month ago was kinda HIGH for a 300 sol/s RX 470 4GB - I paid more like $350 for my PAIR a few months back, though they were on sale at the time.
750 sol/s seems low for a 1080 ti from the figures I've seen reported, unless you're running it at VERY high efficiency settings - at which point it's probably using 50-70% of the watts/sol of that RX 470.
Can't just compare $/sol, watts/sol adds up over time too, especially if you run a rig more than a few months and DOUBLE especially if you don't have SUPER CHEAP POWER cost.
The profit calculation takes into account the power used by the card, 125W for a 470 and 250W for a 1080 Ti. 750 H/s is actually better than the 710 H/s BBT got on a 1080 Ti on ZEC using the Nicehash miner and the card was using 250W.
https://youtu.be/9W3W1YAavSE?t=1402Don't believe everything you read on the internet. The RX 580 and 570's have been available in limited quantites, they do sell out quick though. BBT has built several rigs for his livestream with the cards he's bought and I have four Powercolor Red Dragon RX 570 4GB's that I bought for $190 each being delivered tomorrow. Those four cards that I bought for a total of $760 will do 1200 H/s on Zcash, using ~500W, no comparison to a 1080 Ti that costs roughly the same for 60% of the hash of the 470's. Name a coin and algorithm and I bet the results will be similar.
I'm not going by "what I read on the internet" for pricing. I'm going by pricing QUOTED on cards that are "in stock" by major sellers like Newegg, Frys, Tiger Direct, Amazon - WHEN you can find any available at all.
Yes, if you can find RX 470/480/570/580 cards at close to MSRP they'll hit ROI quick - but I think you underestimate Nvidia as well on ROI, do NOT assume "ETH" or even "ZEC" as the most profitable Nvidia options.
Tradeoff on your 570s is the power useage - for someone with high power costs, the DOUBLE or more power used will eat a chunk of the extra gross income - and if you factor on a SYSTEM level, you're going to need 4 times as many systems which makes the cost comparison quite a bit closer (the 570s will still win on a $/sol basis but by quite a bit LESS than 2:1, while the power comparison gets worse).
If you run the skein or groetsl coins, for most of the last month profitability has been 30-50% higher than ZEC has been for higher-end NVidia cards - and all of a sudden they're pulling in VERY close to the same gross income as your 4 x 570s are.
Nicehash uses Claymore for ZEC, EBWF is faster than Claymore on recent versions - I grant it's not by a ton, but it does seem to be a 5-10% difference on the GTX 1070 and 1080 cards I've done my testing on at the same settings.
I'm not going to go into *what* I'm running my NVidia farm on - but I will state that I made a LOT more on what I'm doing than I would have by running the farm on ZEC - ballpark estimate 50-70% range.
However, that's in a situation that has a VERY small "total network hashrate" that HAS gone up noticeably over the last 2 months, so I'm not sure if the profitability will remain elevated over all other options for another month.
I'll just say that the folks justifiably bragging about their skein-based coin profits last month didn't do quite as well as I did - even though they DID do quite a bit better than ZEC would have done them.