Power supply question

[jason gran]

will a crosairHX 650w support 2 gtx470s sli?

Case: antec 902
Motherboard: ASUS P7P55D-E Pro LGA 1156
CPU: intel i5 750
RAM: crosair 4x1gb 1066
HD: western digital 500gb 7200rpm
Graphics Card: msi twin frozr nVidia Fermi 470 (hopefully sli)
PSU: CORSAIR HX Series CMPSU-650HX 650W ATX12V v2.2 / EPS12V 2.91 SLI Ready 80 PLUS BRONZE Certified Modular Active PFC Power Supply

 

[gordon_81]

i wouldnt recommend it.... a good 750 watt should do it, the gtx 470 is a power hungry card

 

[jason gran]

hmm i just bought the psu less than 3 days ago lol would hate to return and get a bigger 1

 

[jason gran]

ill stick to 1 470 i guess. and when i create my new build with sandy bridge next year ill buy another psu. thanks brotha

 

[jason gran]

Best answer selected by jason gran.

 

[4745454b]

It will be close, but you'll be ok. The GTX470 is rated at ~220W. So two of them should be around 440W. To make the math simple, lets say 450W. Toss in another 100W for the CPU, and another 50W or so for the mobo/ram, and your looking at ~600W for the system. I'm sure as a Corsair it can output most of that 650W on the 12V rail, but having 50W of breathing room isn't that good of an idea.

 

[jason gran]

ok will my 650watt psu run 470 OC'd and i5 Oc'd?

 

[Silvune]

Yes.

 

[jason gran]

you sir ...are the shizniz tyvm

 

[4745454b]

OC'd? I doubt it. You should be fine at stock. A mild OC on the CPU is probably ok, more so if you don't up the voltage. I wouldn't OC the GPUs however.

 

[jason gran]

im just going to buy a 850w corsair hx =\

 

[jason gran]

will the 850 run 2 470s/sandy bridge i7?

 

[4745454b]

Should be fine.

 

[gordon_81]

look at this http://www.anandtech.com/bench/Product/160 look at the bit that shows power usage, a single gtx 470 draws 366 watts on load while playing crysis, the gf100 cards are very power hungry

 

[4745454b]

Not correct Gordon. A SYSTEM with a single GTX470 draws 366W. There is no way a GTX470 can draw that much power.

 

[jason gran]

^+1

I ended up returning my 650hx for a 850hx. so no worries either way lol. gordon should have let this thread die :$

 

[gordon_81]

Not correct Gordon. A SYSTEM with a single GTX470 draws 366W. There is no way a GTX470 can draw that much power.

lol are you sure, that seems a mighty low wattage for a system on load, i myself have an ATI card, so i wouldnt really know, i heard that the gf100 cards were power hungry though

 

[4745454b]

If it were the card only how would it get that much power? 75W comes from the motherboard, and you get another 75W from a 6pin plug, or 150W from an 8pin. To get To get 366W you'd have to have two 8 pin plugs on the card, with the extra 66W coming from the motherboard. Can you link any GTX470 cards with two 8 pin plugs?

The max TDP of the GTX470 is 225W (I think). Most cases it won't go much over 200W. I think the GTX480 is 250-275W.

 

[jason gran]

yes it says Total system power draw

The GTX 470 idles at 33 watts and maxes out at 215 watts, compared with a 27-watt idle and 188-watt max for the HD 5870.