I've googled the problem extensively, but couldn't find a solution (just other people with the same problem, but the only answer they got - if any - was "update your drivers"). With Windows 7, my game looks like this:
OS: Windows 7 Home Premium 64 Bit / 4GB RAM
Graphic board: GeForce GTX 460 / 1024MB GDDR5
I updated the graphics driver several times (latest version: 270.61), installed the most recent DirectX, with the same results.
I tried changing the resolution and frame rate, shadows on/off, reflections on/off, details high/low, didn't help, nor did playing with various compatibility modes.
Is there any way to fix it?