sorry misunderstanding, if you got all the drivers then you shouldn't have a hitch. You may not like it but you may need to turn your graphics settings down, if you have the 60hz option checked try turning that off first as it makes little visual difference and gives you a damn good performance hike also better than losing lighting or resolution. Have you ever visitid tweakguides.com it has a pretty good section on stalker as well as info on general system and graphics performance increases.
I didn't make it!
I will try everything you people said and visit tweakguides.com :) thx all :) and hopefully I don't have to come back to tell it didn't work :p
What power supply do you have? The brand and rating of the PSU also. You would be totally amazed at what 2 GB's of memory will do for you man.