it's still profitable to buy Z9 or A9 ?
i have almost free electricity (0.02-0.03$ per kwh)
is it possible to achieve Payback under 4 month?
any advice?
Returns have halved every ~2-3 weeks. equihash is quickly heading towards "don't mine it", in my opinion.
Z9s still haven't shipped also.
-j
I do not think that they halved every 2-3 weeks. I started mining on one Z9 mini around June 27 and was getting ~ 0.15 ZEC/day. Now, I am getting ~0.085 ZEC/day (I am only running at 675 MHz). In other words, it did not even halved for me yet (after 2.5 months).
Look at the difficulty chart
https://www.coinwarz.com/difficulty-charts/zcash-difficulty-chartI do not see any of the dramatic drops, you are talking about. You understand that we earn less in $ because Crypto dropped a lot. What are you mining now with your GPUs? Perhaps not ETH (LOL)
I should clarify -- some of the loss is indeed in the conversion to USDT -- my accounting is done that way daily due to (annoying) US IRS regulations.
In pure ZEC, I've gone from an average of 1.6-1.9 ZEC/day (7/17/2018) to an estimate of 0.9 today (09/8/2018).
So yeah, not halving every 2-3 weeks, but a marked drop and a continuing downward slope.
I have 12 Z9 minis running currently (~192-194kSol/s pool side) and have 3 Z9s on the way (in theory, if bitmain every ships). I don't regret the 12 Z9 minis, but I'm unsure on the Z9 large units.
You referenced the difficulty chart, which as of this moment shows a 28% 1 day difficulty change, and a 58% 30 day difficulty change. While I realize there is a lot of fluctuation in the rates in a given moment, model out 60% month over month and see how fast your returns disappear. Bitmain is going to keep shipping these until people quit buying them and I expect that the units in flight over the next 30 days will at least add another 60% difficulty...
-j
Just wondering what makes you think difficulty level will spike 60% per month going forward when historically it's only been going up by 20% per month and most recently less than 30% per month as per CoinWarz ZEC difficulty chart:
Considering both the Z9 Mini and the A9 Zmaster have been out for months, do you really think the addition of the Z9 will crank the velocity of difficulty level growth to twice what it is currently ie 30%pm -> 60%pm?
I'm looking into purchasing the Innosilicon A9 Zmaster since they have recently lowered its pricing in response to the release of Bitmain's Z9 but I'm a bit concerned the difficulty level might blow up uncontrollably once the Z9 floods the market. I have access to pretty cheap electricity (5-6c USD/kwh) but still, at 60% difficulty increase the ROI will quickly turn to shit!