4 GPUS on 1 system or 2 GPUS on 2 systems?

[Ivan1982]

One node 2680v3 x 2 and 5x 1080 and other typical stuff, enermax 1700w
One similar node with 4x 1080 is working with cooler master 1000w it was tested with cpu rendering and gpu rendering at same time and there wasn't any issues.

So i guess 1200w is ok for 5 x 1080.

Gpu will never draw full 180W like it's noted it is usually around 60-70% when rendering since memory isn't at full speed so you don't need to worry about those things, same goes for 1080ti, you can run 4 on 1000W PSU easily on single socket system.

Worst thing that can happen is random restart so if you are having 850w PSU and you want to try 3 1080 go for it and if it becomes unstable buy new one.

Take care

[biochemical_animations]

Another idea for the power is to use multiple smaller psu's for the cards. This allows for dividing the power amongst multiple smaller ups units and building circuits.

For example:
I have a 1000w psu for my MB, and two cards, running into a 810w ups and the first 15amp circuit...I've measure about 790 watts max on gpu full render. Granted it doesn't stay at this, but the wattage spiked no higher.

Then, a second 1000w psu powering 3 cards, plugged into a second 810w ups, on a second 15amp building circuit.

Then, a third 750w psu powering 2 cards, plugged into a 650w ups plugged into the same second 15amp building circuit.

Using that kill-a-watt meter I can measure the amps/wattages and everything runs great and doesn't overload or trip circuits.

I actually might have some room on one of the circuits for more, or a small window air conditioner if needed, but for now I think I'm good.

The reason for above, is to go with consumer grade (and priced more competitively) psu and ups instead of one large psu or ups that are expensive. As well, if you run past the limit the building circuit can handle, then your tripping breakers. Plus, if one of those units fail, it's expensive to replace. Plus, by spilling the power like this, the load is not all on one unit, thus perhaps making it an easier burden to carry by dividing it up amongst multiple units.

It's a bit tricker, and requires some testing and measuring, but once dialed in, should run very well.

Doesn't have to be done like this, just a different way to do it.