It is interesting to look at Ethereum with their use of an ASIC resistant mining algorithm.
A reasonable Ethereum mining setup now costs say $1,000 (3 GPUs) and draws about 1,000 Watts. The difficulty is rising rapidly, doubling in the last 2 months. A ROI is starting to look difficult.
So Ethereum is heading back into the ASIC type situation where only those with cheap power can ultimately make a return. It appears just switching to a GPU algorithm is not a long term solution.
That is why Ethereum ultimately plans to move away from pure POW to POS.
630 watts for 75mh 3 r9 390's
$800 for the actual "rig" I bought from Newegg ($799 plus $25ish for shipping to be picky), bit over 60MH at about 600 watts (3xR9 280x) but nowhere near optimised yet.
I am shifting a couple of my R9 290s over to it, as the PS in it is WAY overkill for 3x 280x cards (1350W Enermax Platinum).
To be fair, parts cost would have been higher had I had to assemble all the parts seperately - just the 3 GPU + PS were more priced out seperately than what I paid for the whole rig. 8-)
The thing with Ethereum is that it's the new kid on the block, folks are only starting to jump into it EN MASS recently due to it's price runup, but the hashrate jump hasn't caught up to the price yet. Very nice place for those of us that already had existing hardware or planned "was going to buy it anyway" purchases on tap, not so good for the "Johnnie Come Latelys" that don't have left over hardware from other coinmining or other usages....
