6850 Crossfire Power Requirement

[cammo2066]

Hi

I'm wondering whether my 620W, 22amp (on the 2x12v rails) will be able to run 2 x 6850's in crossfire.

I will probably be over-clocking to prevent bottlenecking if there is any.

Going by this:

http://www.guru3d.com/article/radeon-hd-6850-6870-crossfirex-review/4

It states that 2 6850's in Crossfire, with an overclocked processor, cold calthode lights etc, with GPU in FULL Stress uses 393W.

That can't be right can it?

If it is then I presume I have nothing to worry about.

 

[rolli59]

600 watt is what manufacturers recommend.

 

[17seconds]

Trust the all-knowing Guru of 3D.
As they usually say, their numbers represent a worst-case scenario and your power requirements will generally be less than their fully stressed system. The 6850's are very thrifty when it comes to power usage.

 

[Guest]

22 amps on the +12v rails is a bit low for my liking, but you could probably scrape by.

 

[nged72]

What about an i5-760 OC / 6GB Ram / 6850 CF / 320 HD. Will a Corsair tx650w be fine?

 

[17seconds]

What about an i5-760 OC / 6GB Ram / 6850 CF / 320 HD. Will a Corsair tx650w be fine?

Yes.

Here is Guru3D's power supply recommendation:

Radeon HD 6850 x1
On your average system the card requires you to have a 450 Watt power supply unit.

Radeon HD 6850 x2
A second card requires you to add another ~130 Watts. You need a 650 Watt power supply unit.

Radeon HD 6870 x1
On your average system the card requires you to have a 500 Watt power supply unit.

Radeon HD 6870 x2
A second card requires you to add another ~150 Watts. You need a 700 Watt power supply unit.

 

[rolli59]

What about an i5-760 OC / 6GB Ram / 6850 CF / 320 HD. Will a Corsair tx650w be fine?

Yes!

 

[rolli59]

22 amps on the +12v rails is a bit low for my liking, but you could probably scrape by.

He is saying 22amps on each of the two 12volt rails.

 

[Mousemonkey]

@mzc, start your own thread.