Zarathustra[H];1041924114 said:Well, we've been talking about whether this would be possible on standard 120V 15A home wiring, without using dual power supplies, one each plugged into a different outlet on a different circuit
With a single card in the system at load it drew 802W.
As has been mentioned before, you are only supposed to draw 80% of a circuits rated power as a constant condition, only spiking into full load.
This means the total available power at the wall you can draw is 1440VA. Assuming we have an 80 plus PSU (that is actually performing within spec) the requirement is that you ahve at least a 0.9 power factor, meaning the most you can draw froma single 15a wall outlet to a PC power supply is about 1296W.
Not sure you'd be able to add a second one, without a second PSU, on a separate outlet residing on a separate circuit.
Power factor is not the right term to use here. That is something entirely different. (Has to do with the phasing of the current draw vs the phase of the voltage sinewave)
The word you are looking for is simply efficiency -- 90% efficiency in your case.