When I first bought my computer it had Vista on it. After a while, when I tried to play games the computer just closed them because of some "critical error". It also told me that my graphics card (nVidia geForce 7500 LE) was to blame. Okay so I downloaded the newest driver. Didn't work. Then after being unable to play games for some time, I decided to get a new graphics card (8600 GT). Didn't work. I dowloaded the newest driver for it. Didn't work. So then I decided to install XP on my computer instead of Vista cause maybe it was just the OS. That way my harddisk was also formatted wich would rule out a software error. After getting XP this problem came instead of the other one (see img).
After a few minutes of play the textures mix up. If Tab+alt out and then in again they turn back to normal. But suddenly the computer takes half a minute to change from the game to the desktop!
Why is this happening?! I the newset driver several times. I even tried underclocking my graphics card, but still I have the same problem.
I hope someone has a solution.

have you had a browse around the cards control panel and adjusted the settings ? if not right click on an empty paret of the desktop and select nvidia control panel if you card has the option to enable physx enable it if it ie enabled try deselecting it and try your game again , when you downloaded the drivers did you manualy enter the details on nvidias website , if so go back to the site and select option 2 let nvidia scan your system and see if the driver you installed is the correct one

PS: this happens in all games.

Neither worked but thanks anyway..

I don't know about nVidia, but ATi has an option to force AA. If you can, disable that option in the nVidia properties. Clock speed shouldn't be the issue here. Do you have DX9 or 10? Sometimes there can be compatibility issues.

Your video card is AT BEST marginal. Upgrading will probably do more for our gaming ability than most anything.

The problem is just that a bad graphics card does not cause that (refering to the picture). My MSI WindBook can run Warcraft (just to use that example) without any problems. But with poor graphics of course.