video error?

[tippenein]

Setup:
Windows 7
directx 11
ATI 5770 video card

I have updated drivers for ATI, directx, steam etc.
I also tried using native mode and it works smoothly with no crashes.

~ The crashes happen at seemingly random points once I enter a game
~ The screen will freeze, followed by (usually) a gray screen with faint white vertical stripes
~ sometimes it will recover from that, but usually it will stay frozen and eventually the monitor will read 'no monitor input' or w/e
~ thought it might be temperature, but it holds steady around 43C system and 30C cpu during gameplay

I've tried disabling almost all of the video options (force vertical sync, pixel shaders, start windowed, load textures on demand) as well as all different levels of quality in-game.

Any suggestions would be appreciated. Thanks

[zagibu]

I also have a strange video related problem with Warband (besides regular other crashes and connection losses). For me, the same two frames are played over and over again, as if a LP had a scratch and the needle jumped on it. Very annoying.