Quote from: Xian on June 07, 2011, 09:04:06 PM

thanks xioros for your help.

Here is the layout of my mobo:
http://upload.wikimedia.org/wikipedia/commons/f/fc/PCIExpress.jpg

First slot is x4. I don't exactly know whether it's physical or electrical.

Those slots are (depending on a jumper setting) either:
x4 physical, x1 electrical
x16 physical, x16 electrical
x1 physical, x1 electrical
x16 physical, x2 electrical
or
x4 physical, x4 electrical
x16 physical, x8 electrical
x1 physical, NOT USABLE
x16 physical, x8 electrical

In theory you can use all four of them for GPUs with the first setting, the x1/x4 ones with extenders of course.