I really don't understand people who are pouring 10s of thousands into this like they can make it to be more than a hobby. The current profitability is a temporary glitch that will disappear by the end of the year. For profits to continue anywhere near like they are now requires the price to keep rising at least the same rate as the difficulty. Once the price stabilizes, profits WILL plummet and unless you have dirt cheap electric you will never get a ROI.
It's really that simple and straightforward. For those with electric more than 10 cents a kw, who are thinking of putting together their first rig, do you consider it a hobby or do you seriously think it's gonna make you rich in the long term? If the latter, what on earth makes you think prices will keep rising indefinitely??
I have money invested in cryptocurrencies. That might make me rich in the long term. I'm also putting together my first rig. Purely for fun but with the hope that I might make enough to pay for the parts before it becomes uneconomic. I rate my chances of break even to be 50/50. I will be very surprised if I make much more than that.
I really wish there was something I'm missing that will prove me wrong. But in the absence of such, the stark facts are inarguable. When the rate of price increase drops below the rate of difficulty increase, profits will plummet. Tulips don't appreciate forever and neither will cryptocoins.
I know a guy with 600 GPUs. It can be more than a hobby, but you need to look for low electrical cost, and think of the return in terms of 6-12 mo intervals. People who were already mining before the profitability increase are sitting pretty right now. You can always colocate. I know a place in sweden where I can get power and rackspace in 10KW increments for $750/mo (in an actual datacenter not a ghetto mining warehouse). The mining warehouses run a little cheaper around $60/KW but they don't want to deal with custom GPU solutions because it's a PITA as they don't put in PDUs with remote reboot functionality.
Also, my past experience has been that people quit buying GPUs once it takes 3-4 months to get a full return. The problem in the present situation is, people are gauging their buy on current profitability without taking into account the 100K other people doing the same thing. They'll all buy every AMD gpu they can get their hands on (people are even mining on 560s now) difficulty will go through the roof and no one will be mining at a profit. I expect to see a lot of RX570s and RX580s on ebay in the next 3-4 months.... This is a situation I've never seen before where there was an extreme shortage on mining equipment. When these kinds of situations happened with bitcoin it was different because there, the ASIC hardware rolled out in increments. None of those companies had/have the production power of AMD. The next million or so gpus that amd makes are all going to end up mining ethereum doubling the network hashrate and difficulty along with it.
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