Dual PSU and Load Balancing

[TigerLord]

I am about to build a system with four 290x and an overclocked CPU. Since they do about 300W each under load, that's 1200W just for the cards, and ideally, they say you want to keep total consumption below the 80% mark for which the PSU is rated for.

So even with a 1500W, that leaves me 1200W, just enough for the GPUs. The hardrives and CPU are not even factored in yet. I'd like to get two 1000W instead. I installed a new 20A breaker in my panel with the appropriate wiring.

Is there a way to have both load balance the entire rig?

Or do I plug one in the motherboard, and use the paperclip trip to power the other PSU and use it to power two cards?

I tried looking for an adapter that would replace the paperclip but they all seem to be PSU testers, not meant for load balancing or dual PSU rigs.

I'm hoping to power 7680x1600 with those cards and will get the ASrock Extreme 9, which has four Pcie 3.0 (five, actually, since it uses two PLX chips).

 

[Deleted member 88227]

They make adapters that allow you to plug both PSUs into the motherboard so when one powers on they both do. You'll want to do the rest of the "load balancing" by plugging xx number of GPUs into one PSU and the rest into the other.

 

[dragonstongue]

just for 2 gpu alone a GOOD 650+ should be fine, something that can run 24/7 loaded, so in that regard something like AX750(which is gold rated) a Seasonic x760 or some such for 2 gpu
and then the other another 850+ should be fine.
no need to have 2x1kw psu IMHO, gpu 300w per is rated they can draw a little more or less but average 315 if I recall gaming load or 26.25a per obviously if you overclock them it will increase this but declocked some will also lower this.
300x4 1200w
cpu another 300w pushed to breaking ~
rest of system should be 150w tops I would imagine
so 1650w
that's 825w per any decent 850 can provide this, most gold rated 650 can push to hit 800w delivered, good to great 750 can provide easy 850w provided.

As Skillz stated they make adapters so 2 power supplies can power together at the same time, many folks I have known use this style of setup, recently I had a buddy who had TRI 480 and a full system liquid cooling with a 980x cpu tri rad for 2 gpu dual rad for 1 gpu and cpu.
power to cpu, liquid, system via a 750
power to gpu 1kw(I believe it was an HX1050)

 

[Deleted member 88227]

I thought I posted a link to such an adapter, but apparently I forgot.

here

 

[Nenu]

There is no load balancing other than what you connect each PSU to.
The PSU adapter will turn on a second PSU, it doesnt control or influence anything else.

Dont connect PSU ouputs directly to each other as they will fight each other to maintain slightly different voltages.

 

[TigerLord]

Many thanks for the explanations + adapter link.

I was under the impression both PSU had to communuicate with the mobo to properly power components but apparently it's not even that complicated.

 

[dragonstongue]

well the motherboard still is kind of communicating via the lines themselves, the pins(I think was 21-22 and 22-24) tell PSU to turn on same concept as paperclip to short it, the adapter does the same thing in that the pins in each 20/24 pin ATX motherboard connector "sense" when they should turn on, so they do.

I know many folks that have done this for various reasons being stupid high end configs, sick storage servers etc, it works well with proper adapters rather then ghetto mods that have a much higher chance of failure, there is that benefit as well that if for whatever reason you do not want the gpu to be powered up or whatever, you can just unplug the one atx power from the adapter and it should be just fine so you can replace, upgrade whatever.