(RESOLVED) Penumbra Performance Problems?

[Thaliur]

I can't see any reason for the tech demo -> Overture performance decrease, but the Framerate differences in Overture seem to be caused by what you could see if it was bright enough.
Maybe a texture pipeline issue, or something about the physics calculations (though these would also occur when you're not looking at them, so I guess it's not their fault).

This is weird.

Maybe it isn't a problem with your graphics, but with your sound chip. Some sound chip have a hard time handling directional audio or environmental effects (especially OnBoard-Chips).
The old mine has a lot of natural sounds, at least I got that impression, and maybe when you turn towards that dead end, some of them have to be processed intensely.