XFire PCI-E Speed difference ?

[Brizzles]

Is there a great difference between running crossfire in :

8 x 8 slots

16 x 4 slots

The new P67 seem to support either of the 2 i've mentioned.

HD 5850s' if its relevant.

Cheers.

 

[muggs]

i know between 16x16 and 8x8 theres nothing really

 

[Scougar]

I wouldn't want to run in a x4 slot. Times x8 is fine. I doubt there will be that much difference on the x4, but why limit yourself?

If there was the choice between the x8 x8 if you know you are going crossfire, I would get the x8 x8 rather than the x16 x4.

 

[MoRT489]

@ x8x8 takes only approx 5% hit (vs x16x16) but x4 is much more iirc from people trying this previously.

EDIT: not as big a hit as i expected, game dependent:
http://www.techpowerup.com/reviews/AMD/HD_5870_PCI-Express_Scaling/25.html
http://www.tomshardware.com/reviews/p55-pci-express-scaling,2517.html

 

[ThomasTheTankEngine]

I wouldn't want to run in a x4 slot. Times x8 is fine. I doubt there will be that much difference on the x4, but why limit yourself?

If there was the choice between the x8 x8 if you know you are going crossfire, I would get the x8 x8 rather than the x16 x4.

There's a big performance hit when using a 4x slot. So much it's not really worth sticking a second card in there.

If you want multiple graphics cards, you've got to get a mobo that does x8 x8 or x16 x16.

 

[Ezyryder]

does any P67 board do 16x16x?

 

[jamesfreddie]

No diffrence

 

[MoodyB]

Comparison of X58 & P55 pci-e speeds.

http://www.tomshardware.com/reviews/p55-pci-express-scaling,2517.html

 

[pingu666]

the msi gd65 and the asus higher end mobos do 8/8

 

[555BUK]

There will be a difference, but only by a few percent.