Intel P35 chipset + newest GPUs

Hi,

I'm about to build a low-cost rig for GPGPU usage. I wonder, if motherboards with Intel P35 chipset (which has PCIe 1.1 bus) are able to host the newest PCIe 2.1 GPUs?

For example: ASUS 6950 DCII gpu + ASUS P5K motherboard. Compatible?

 

They will work, just with some small performance losses. For GPGPU you should hardly notice it. Just be careful nothing you're running is CPU-bound, if you've an old slow Core 2 Duo or Pentium D in there, you'll very easily bottleneck such a powerful graphics card.

 

Ok, thanks. How about using the PCIe x4 port for another GPU? Would it bottleneck GPGPU computing?

 

For PCIe x1, yes it will. How much depends on the GPU, and the task, but you may see 20-40% drops in performance using that interface.

 

The Asus P5K seems to have 2 x PCIe x16 ports (blue @ x16 mode, black @ x4 or x1 mode). How do you determine whether it's using x4 or x1 mode?

 

As far as I can tell that just means it is designed to be used with 4x or 1x cards, and it will run at 4x whenever you put a 16x card in there. If it is genuinely 1x, then that's obviously even worse.