I have my Titan running on 2 x EVGA 750W G2 80+ gold PSUs.
According to the miners own readings, it is using a total of 1050W.
That's split between 4 cubes, not exactly equally but close - between 255W and 268W each.
That's fine. Being 80+ gold PSUs I would expect the power usage at the wall to be 12 to 13 % higher than this.
I'll cheat with the figures here because it makes it easier, but the principle should still hold.
Assuming a total power draw of 1050, split between 2 PSUs
1050/2 = 525W per PSU
525 x 1.12 = 588W per PSU at the wall
This should give a total draw (2 PSUs) of 1176W
My killawatt is showing 1550W to 1630W at the wall.
What might cause this ? Are the PSUs on their way out ?
Possible errors in my calculation are that I don't know whether the controller power is included, but a RPi doesn't pull 300W. I also have a large fan moving the hot air away, but this pulls about 30W and is not powered by the EVGAs anyway. I've tested its draw by unplugging it and power at the wall only drops by 30 - 31 W.
Any clues would be appreciated. I have some new cables on the way so that I can use another 2 PSUs giving each cube its own PSU. Hopefully this will bring the EVGAs usage down, but they should only be using about 70% capacity anyway.