I'm very interrested in lowering power consumption for 570 and 580s. On my nvidias i'm able to get 270Mh/s at 750w (would be lower, but cooling fans makes about 80-100w!)
On my RX rigs it is trrible, I get ~1650w at 350Mh/s while in cool environment it can get as low as 1450w so 200w just for cooling!!, but still 1450 base for one 12gpu rig seems very high to me. Also in this case I have 3 psu from times of dual mining, and only 80plus gold, so that can be quite a lot wasted, maybe another 200w? I don't have physical access to switch to 2 psus anymore and even if I did there is risk of some gpus not booting and time to troubleshoot it just not worth it.

I'm writing about real power consumtion, aproximated from about 24h. Not some virtual numbers from hiveOS/hwinfo etc. My numbers includes about 20-25w of "system" consumption.

I'm not able to get 850mV@1150mhz at any of my amd cars, i think 880mV (I tried lowering mhz to 1100 and gpus still crash, but upping voltage helps) is lowest i'm able to run stable. Stable for me means at least 15days without miner restart, i don't measure stability in hours.


So as you can see, with my rate of about 0.85usd/kw I barely manage to be profitable. Still easier then selling rigs though.