It came as a shock to the good folk down at Memory Express, but the RX580 GPUs draw roughly 200-250W each when running under Ubuntu 16.04. Under Windows, a 1200W power supply is sufficient. Under Ubuntu, the rig will reboot after 5-10 minutes when power requirements outpace the PSU.
Sadly (and gladly!), with Ethereum trading as high as C$1300, miners have cleaned out stock in Calgary. Memory Express isn’t expecting new 1500W PSUs until February and I can’t fit two smaller units in my existing frames (see the specs on my aloha and bula rigs).
The rigs are stable with 5 of 6 GPUs attached. Each card is getting roughly 22 Mh/s under current software configurations. This is all in accordance with manufacturer specs (no BIOS mods).
Apart from adding a PSU, options include:
- Installing Windows (not a chance)
- Undervolting (difficult in Ubuntu, but apparently it’s possible)
- Repurposing two GPUs (mining Monero might be interesting)
- Waiting for driver updates (preferred)
aloha and bula are chugging along just fine at 108 Mh/s at five-sixths capacity. Ether is being mined, but not at the pace anyone would like (0.013-15 ETH/day on Dwarfpool).
Interestingly, the Red Dragon RX580s draw slighly less current.
Sister rigs bunking in a salvaged server cabinet.