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Multiple power sources question


#1

I’m new in this forum.

Please imagine this situation. You want to power one computer with multiple connected GPUs but you don’t have a single PSU able to provide enough power to the whole system. But you do have another PSU laying around and the power of both combined would meet the computer power requirements. None of those PSUs cannot even power the CPU, disks, etc, AND each of the GPUs at the 75W max power draw that a PCI-e connector allows.

In this case, the 2nd PSU could provide enough power just for the GPUs through the additional 12V connectors on the GPU boards.

Would this work? The load balancing would be automatic or some extra hardware would be necessary to manage that? Thanks.


#2

Well, you would need a way to power on both PSUs at the same time, either mod it yourself or adapters are available.

As for the load, the motherboard power probably should all come from the same psu, however, drives, and GPU supplementary can come from either. Check that the first psu can supply everything on the motherboard(PCIe slot included), if not time to buy a better psu. Then for the gpu’s, check what the power draws are, minus 75w each for the slot, then add any drive wattage plus a buffer(whatever you feel is safe), and see if your secondary psu is good enough.


#3

Just google for ‘psu jump wire’ to tackle the power on issue


#4

This is the solution. Can also buy power cords that have 2 female plugs wired to a single male so you don’t need 2 cables/ This is common with enterprise hardware. As long as each PSU can hold up it’s end, you should be good. Might need to jump the 12v mobo connector to supply power on other leads, but definitely doable.


#5

something like this is what it sounds like your after.

turns on the slave power supply when the master power supply is turned on


#6

Enter the Antec High Current Pro Platinum.

It has a “OC Link” cable that basically is a tandum jumper that powers on both PSUs at the same time. This is included in at least one of 2 PSUs you might purchase, so there’s a high likelihood this works without buying specialized modular ATX cables.

store.antec.com/highcurrentpro/hcp-1000-platinum.html