I installed System Shock 2 and when I try to play the graphics are plain weird.
I know my graphics card sucks, but still the game should play fine. Can someone help?

My laptop:
Genuine Intel CPU T2130 @ 1.86GHz
2,7GB RAM
SiS Mirage 3 Graphics card

yeah, I think this is a good time to revert to DX6 rendering, edit cam_ext.cfg with notped and change into also, make sure you are using the latest GPU drivers.

I did that, and it was the same.
As far as I can tell everything is up to date.

What's weird is when I got the game a few months ago, the same thing happen, but sometimes, it worked fine. And Some textures/graphics look fine, like the elevator ones. I'm not sure what is the really problem :S

pretty sure it's the obscure gpu, and/or its drivers.

try enabling windowed mode, change into in cam_ext.cfg (the one in your SS2 folder, NOT the one in docs).

if that won't help. try renaming cam_ext.cfg into something else - this will make the game go into sort of oldschool mode, and it woked even on a voodoo3 this way, so unless something is horribly broken, you should see at least some improvement.

small bit of history - SIS had the potential to become the third gpu player, they've had some pretty ok integrated graphics chips, and even full standalone lowend/mainstream cards, but the driver quality was not sufficient, causing them to lose sales to ati and nvidia, so they've faded away after the Xabre series.