In my warehouse, I have asked my electrician to give me 20amps per circuit.

During my 1080ti farm deployment planning:

One circuit ==> 4 power outlets

4 power outlets ==> 5amps each maximum load.

5 amps x 220v = 1100watts per outlet

1100watts ==> 1 rig

Apply 20% buffer to keep your PSU safe, no stress and working for a long time 24x7

1100watts x 80% = 880w

1 rig ==> 3 x 1080ti = 880w including power mobo, cpu etc.

Assume mobo, cpu, etc consume 150 watts, 730 watts available for GPUs

730watts divided by 3 = 243watts each (3 x GPU rig)

or

730watts divided by 4 = 182watts each (4 x GPU rig)

For every circuit, you can now power 4 rigs with the specific amount of "firepower" you need...

So a 3 x 1080ti powered all the way up to 243watts will give you decent hash.

The 4 x GPU rig, IMHO is the best hash ratio.

Phil - can you help double confirm my calculations.

BTW, USA power rating usually is by default 120v while UK and ROW mostly 220-240v format.

For my 1070 farm, I think I will go for density because these cards can do very low tdp with very good hash ratio.
Thinking of 9 x GPU rig below 2000w-2100w or slightly over 10 amps...

----
scrapbook: 199CRmTihjCptayc5v3mLTiLEJ6k88eyXb