Hello! Sorry for a stupid question. I am not good in hardware. The question is the following i have 4 video cards

1) GF 7950 GX2 1 GB DDR3

2) same as 1

3) GF2 GT630 2 GB (http://partsurfer.hp.com/ShowPhoto.aspx?partnumber=702084-001)

4) GF9600 GT 512 Mb DDR3

I may use 2 of them. Please help me!

Million thanks in advance!