How much wattage do two crossfired 7950s require?

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1

I'm building a new system and I was wondering how much wattage two crossfired 7950s require. I'm considering purchasing another 7950 to put into the build later but I'm not sure if my 750w power supply will be enough to power a dual GPU system. Also, if my PSU is enough, would it be worth it? My mobo only has one PCIE x16 slot so I would have to put the second card in a x4 slot.

  • AMD FX 8320
  • SAPPHIRE 100352-3L Radeon HD 7950
  • Corsair H100i
  • GIGABYTE GA-970A-D3P
  • Corsair HX 750
  • G.SKILL Sniper Series 8GB (2 x 4GB) 240-Pin DDR3 SDRAM DDR3 2133
  • Kingston SSDNow V300 Series SV300S37A/120G 2.5" 120GB
  • Seagate Barracuda 7200rpm 1tb HDD
  • ASUS DRW-24B1ST/BLK/B/AS Black SATA 24X DVD Burner
  • Fractal Design Arc Midi Arc 2

 

2

750w is relatively fine. But if you want to be more secure grab an 850w PSU. Besides if you upgrade in the future it'll be worth it. Especially since you have an AMD build they do take up fair amount of power.

3

That's more than enough for a crossfire system. Their is no reason to upgrade it even if you overclock everything.

4

I plan on getting an HX-650 for my build with an 8350, which I will eventually crossfire 7950s. You could probably get away with 550W or 600.

5

We all did the math a few months ago, Me, Gigabuster, and (I think?) Brennan. And you can get away with having crossfire on a decent 450 watt.

6

That PSU would be enough for 3 way crossfire.

7

That PSU is perfectly fine; like Berserker said, it can handle 3 7950s. The HX series are very well made, and can crank out even more than 750W while being within ATX spec. This system will probably pull 580W from the wall at stock, 650W max when OCed.

8

If you whant to crossfire 2 HD7950's you are going to need a better mobo that one is junk 

It has a pcie x16 slot that will run at x16 speeds and anuther will run at x4 speeds + a fx 8320 will be better off on a mobo that dosent have a 4+1 power phase (anless you allways what to run the cpu at stock)

9

Thanks. If I get another 7950 to crossfire I'll get another motherboard