Graphical Issues

[jr0026]

Greetings, I'm having some graphical problems which can be seen on the pictures attached. The first one in the demo happens when I get to the part when there is a corridor and suddenly it is filled with water and a monster is coming to end my misery. The second one can be found throughout the entire gameplay when encountering torches and any other light sources. It's very frustrating because I can bearly see anything because one second the flickering fire illuminates a big part of the area and when I move than it is pitch black again(sorry my english is so messed up right now and I can't really express it I hope you know what I mean from the picture).
I'm using an ATI RADEON X700 PRO on WinXP 32bit.

I thank you for your help in advance.

I also have the problem of where torches and other lights will work but when I move a few feet from them or stop looking at them, everything becomes completely dark (not pitch black, just much darker, as if the torch disappeared). I have had no other problems with the game at all. I have Vista 64 bit, ATI Radeon 5870, on an Intel x58 (Core i7) motherboard.

Edit: It might be interesting to note that I tried taking a Fraps video of this issue, but when I played back the video it appeared to work as intended (i.e. the problem was strangely missing from the recording).