Steam Penumbra: Overture, Black Plague & Requiem

[Thomas]

Please say what graphics card you have.

This is some problem with the OpenGL drivers. Try this:

1) Download the latest drivers for your graphics card:
2) Uninstall the graphics card drivers.
3) Restart computer
4) Install new drivers.

Unless you have a really old card, the game shall work. The problem lies in the drivers.