Artifacts/ gfx corruption in "simple" games

[Jet boot Jack]

By "simple" I mean graphically undemanding. Games such as Thief 2, Duke Nukem 3d and Machinarium.

So ye... hi there

These games starts ok but in a matter of minutes turn unplayable as the whole display goes corrupted with white noise and horizontal bars/ artifacts.

The corruption persists after exiting the games (albeit in a mellower form) and is not fixed till restarting.

My card is a Sapphire 6850.
Temps are reasonable.
Drivers up-to-date.

The issue does not occur with newer/ more demanding games. That and the fact that I tried to take a screenshot of my corrupted desktop but the saved pic shows a perfectly normal desktop, leads me to believe it's a software, not a hardware, issue.

Can you help me point the culprit?

 

[auntarie]

If you are using Windows 7, some of the older games that were produced before win7 are not compatible with it, or at least not completely. The problem might be that they can't utilize DX11 completely or something of the sort.

 

[Jet boot Jack]

Oh ye, I knew I forgot something- I've vista 32.
And the games SHOULD work, even on win 7, as they're from GOG or steam.
(and Machinarium is relatively new)

 

[auntarie]

Then I don't know man. Sorry :/