problem with high texture games.

hi

When I play games with alot of textures (like eq2 and oblivion) I get a layer of static over the 3d rendered areas. Note that this doesn't extend to the 2d parts of the game like inventories, and menus and such; just the 3d parts. The games are still playable but look pretty ugly.

I've updated my drivers as well as directx all to no avail. I have not updated my BIOS but I'm not sure that would help anyway. Any ideas whats causing this?

Here is my specs:

Amd64 4000 2.4 gig
geforce 7800 gt (which i think i may have just fried by trying to fix this myself. but thats another problem)
2gigs ram
asus a8n premium mobo

Any help is appreciated