Direct 3d Problems on 7600 GT

Hi

I am having some terrible problems with direct 3D and wondered if anyone can help. The problem started on my 7300GT and have contiued since i upgraded to my 7600GT. the games start fine and i am able to navagate through the menusset up my options and start the game but the momment i enter the game all i see is a black screan and my cursur. The screen resolution appears to be 640x480 which is not what it is set at in the options. The same thing is happening on the following games

Battle for middle earth
Battle for middle eart 2 plus expansion packs
Mohaa plus expansion packs
Call of duty
Command and conqour 3 plus expansion packs

But Call of duty 4 runs fine every single time i run it

Anyone got any ideas

CPU Spec

Athlon XP 3000+
GIGABYTE GA-7S748
2 GB DDR PC3200
160GB HDD
CLUB 3D 7600 GT
Sound Blaster Live 5.1
Netgear FA311TX
450W PSU

Many Thanks

pagenslave