PSU quick question...

[matchettman]

Quick question RE: PSU -

I plan on getting an ivy bridge CPU (probably o/c'd 3750k) and a mean graphics card like the nVidia GTX 690 (or 685 or whatever they call it)

My question is what PSU power will i need to run these components safely? I was thinking something between 650-750W...

Baring in mind i never want to go down the SLI route (i will have a 1TB hdd and a 120GB SSD and mid range MB if that also makes a big difference) just dont want to spend money on a 850W PSU if i don't need that power.

Thanks

 

[cmndr_andi]

When you say a GTX 690 do you mean the upcoming GK110 GPU or do you mean a dual-GPU (most likely one using two GK104 cores)?

For the former, I would go with a good quality 650W PSU. For the latter I would go with a 750W-850W PSU, based on the high power consumption of previous Nvidia dual-GPU cards.

 

[matchettman]

Aha that kind of answers my question anyway - i meant dual GK104s for the 690...assuming it would be the most power demanding...so your recommending 750W or 850W - that's really interesting that dual GPU cards need that much! I would have thought SLI would have been the only reason to need 750W or more but suppose it's best to be safer with that power rather than going for 650W and losing out.

Cheers

 

[cmndr_andi]

Well a dual-GPU card is a SLI system - it just happens to be carried out on the card (though the cores are generally underclocked and undervolted from the stand-alone versions to fit within the heat dissipation capacity of the cooler).

This review shows that the maximum system load power consumption (of a bare-bones i7 system) with a GTX 590 is between 500 and 600W. So if you are running a pretty bare-bones system and don't mind the PSU being brought relatively close to it's limits (where it is less efficient and noisier) then a 650W would probably be OK. However, taking into account the PSU efficiency and noise (as well as the headroom for upgrades) I suggested a 750-850W PSU.