HD 4850/4870 Crossfire on Asus P5W DH

[Darth Nemesis]

I have an Asus P5W DH (975X) motherboard with support for x8 + x8 crossfire. I am planning to go crossfire with HD 4850 or 4870 cards.

Does this motherboard support crossfire for these new breed of cards? I am asking because I have heard a rumor that some PCIx 2.0 graphic cards do not work properly in the second PCIx 16 slot on this motherboard. Provided it works, would there be any serious performance limitations due the usage of x8 mode for crossfire?

I have decided to try and hold on to my P5W DH and E6600 till the time X58 mobos and Nehelam processors are launched.

I have a 20" LCD, so for the time being, will be mostly playing at 1680 x 1050, all settings at max possible level. But I also have plans to upgrade to a 24" display around oct or nov. So does it make sense going for a 4850/4870 Crossfire with my present mobo?

[dennismagic]

I have an Asus P5W DH (975X) motherboard with support for x8 + x8 crossfire. I am planning to go crossfire with HD 4850 or 4870 cards.

Does this motherboard support crossfire for these new breed of cards? I am asking because I have heard a rumor that some PCIx 2.0 graphic cards do not work properly in the second PCIx 16 slot on this motherboard. Provided it works, would there be any serious performance limitations due the usage of x8 mode for crossfire?

I have decided to try and hold on to my P5W DH and E6600 till the time X58 mobos and Nehelam processors are launched.

I have a 20" LCD, so for the time being, will be mostly playing at 1680 x 1050, all settings at max possible level. But I also have plans to upgrade to a 24" display around oct or nov. So does it make sense going for a 4850/4870 Crossfire with my present mobo?

Even P45 (PCIx 2.0 x8 + x8 crossfire), bandwidth is still not enough for 4850 crossfire.when compare with x38 or x48(16+16), for the crysis and WIC, there is huge difference in FPS!

975 is PcIx1.0 8+8 so it is equal to PCIx 2.0 4+4,

[ultimeus]

PCI xpress 8x 2.0 = PCI xpress 16x 1.1 bandwith is the same.

[Hiredgoon]

I have the exact same qustion. I have the p5wdh deluxe and I guess its sucks for crossfire, also have the e6600, woot!

[xMrBunglex]

that motherboard is not bad for CrossFire. i had the same mobo when i first bought my 3870's and CrossFire scaled perfectly on it. i don't know how much more bandwidth the 4K series cards will use, but i can tell you for a fact that my 3870's were perfectly happy with x8/x8 PCI-E slots. the only performance advantage i got when i bought my X38 motherboard was from the higher FSB it let me hit and the faster RAM.

[Eniqmah]

See sig.

[non]

Even P45 (PCIx 2.0 x8 + x8 crossfire), bandwidth is still not enough for 4850 crossfire.when compare with x38 or x48(16+16), for the crysis and WIC, there is huge difference in FPS!

975 is PcIx1.0 8+8 so it is equal to PCIx 2.0 4+4,it doesnt go linear like that. 975 is still good for CF because provide load balance unlike P35. But of course scaling will be reduced, wont reach X38/48 level.