graphics corruption

Hay all.

The last few days some thing funny bin going on in cov

At first it happen some times when i loaded into a mission and there be funny colors and brightness all messed up.

So i had to restart cov to get it working as normal again.

But just now this also happened when i was street hunting

http://img529.imageshack.us/my.php?image=wtfuwc.jpg

My graphics card not over heating its never goes over 60c


Gpu is ati 4850 with cat drivers 9.2

Thanks for any help