Problem with the graphics

[El Prima Fax]

Greetings.

The problem: Whenever the game enters time around 4:00 or so, for some reason everything is covered in purple/blue blob.

Like this:

And when it returns to daytime, the problem is fixed. Also, on some interiors annoying lines appear over the screen from the 3d models and sometimes even make certain meshes disappear.

Like this:

The blue glitch has appeared just recently, and the 'line one' has been there since the beginning.

Anyhow, updating my GF6600 drivers didn't help, and I have DX 9.0c installed.

Any ideas?