graphics are screwed up

Hi, i installed nvidia's latest driver for my 6600gt yesterday and i noticed that the pixel shader effects on the water were corrupted or not looking quite right. the game ran ok but i lived with it.

i went to play sim2 nightlife and the game would load but no graphics would be displayed.
so i then decided to take a look at half life 2 and the same problems occurs where the front end doesn't display.

it should be noted that all games did not display any front end intro videos, just a blank screen. i uninstalled the new drivers and went back the old ones, however the problem still persists and i'm not sure what to do other than reinstall windows; which i dont wanna do.
also, i dont use windows restore so thats not an option. i dont have a clue what to do about this.

any help would be greatly appreciated

is the graphics card oc`d ?

nah. i got fed up with my system not being how i like it so i decided to reinstall windows

just finished reinstalling everything and the problem still persists, i believe its a problem with the new drivers that i have installed, they are the latest from nvidia and via (for my chipset)

since you reinstalled windows did you reinstalled directx9c?

yeah, still the same. im currently running through the process of putting my old drivers back on, i've just reinstalled the graphics card which yielded an improvement, i'm about to change my motherboard drivers

update, it turns out the problem was caused by VIA's new driver set. it includes an AGP driver which it turns out is a load of crap, i went back to an older version and now my system works fine. thanks for the responses

how hot is your 6600GT ( recall something about a wobbely heatink )

its fine, very secure. ive sorted the problem now, its related to VIA's latest chipset drivers, it appears they decided to put their own AGP driver into the driver set and thats what messed things up for me. i went back to an older set and its fine now