Will a EVGA 9600GT SSC work on my motherboard?

Yes, the 9600gt will work. All PCIe 2.0 is backwards compatibale with PCIe 1.0.

Thanks! Does the crossfire thing means that the motherboard is ATI only, because I bought this card a month ago and I'm seeing all kinds of colors and geometrical figures every second time I run a game. That is... I boot the computer, run any game (just fine), quit and run any other game and boom! Geometry 101 stars showing on the screen! If I wait the game closes and throw me back to windows in 16 colors mode or the computer crashes. Some times when this happens and I restart the computer Dr.Watson says sometning about a "thread stuck in the device driver". I have the latest Nvidia drivers! Plese help! Do I need a new card?

^Have you re-installed the drivers? And yes CrossFire is only for ATI cards. The nVidia equivalent is SLI.

@OP: Mind listing PSU,etc?

Yes, I downloaded the drivers a week ago (181.22). I know I can't use 2 Nvidia cards with a crossfire motherboard, but can I use it for just one (normal use)? I was playing Test Drive unlimited just now and the computer crashed. It was showing blocks of different colors all over the screen and sound kept going in a loop. Is the card malfunctioning?