Flashing black lines and triangles.
 

http://hem.bredband.net/b239761/prey.png

Multiply the triangles you see in the ss with 1000 and insert some black lines there as well, then you have what the game really looks like for me.

spec: I 2600K, GTX 680(Fw 301.42) and win7-64.

Have tried v-sync on/off in both game and nVidia cp.

It's been 5years since last playthrough and I really want to play it again.....not watching some playthrough at Youtube :)

Any ideas?