blank screens

[thethisguy]

I have recently reformatted my computer, and a result of it was my computer's "inability" to run games operating under directx (more specifically, Need For Speed: Most Wanted, Halo, Age of Empires 3). When I run these games, they appear to start up fine but after clicking the shortcut, the screen goes straight to a black screen, while the game music and sounds are still playing in the background. The funny thing is, when I alt+tab out of the game onto the desktop, I can see the main screens of the games really quickly before it minimizes. I have re-installed all video card drivers, motherboard drivers, as well as latest directx (9.0c). Any help would be appreciated.

specs:
Gigabyte K8NSC-939
ATi radeon x800 pro
AMD athlon 3500+ @2.2
1 GB mushkin ram
200 gb western digital harddrive