Before Chrismas last year, I had no problem running Warhammer 40k Dawn of War/Expansion and/or any game that required a 3D card. Stopped gaming while I was in classes other then the generic 40 hour marathon of regular console RPGs (no PC games for me during the school year, usually). Time passes, summer rolls around, Heroes of Might and Magic V comes out. Supposed to run on my PC (didn't know the game was bugged all to hell), didn't quite workout, update all my drivers (video card, sound card...)

Sadly now, none of my games work on my PC. I reinstalled my old drivers rather then the newest, shiniest drivers (since it actually worked when I was using them), yet I still have horrible lag every 5 seconds on gameplay in Dawn of War. I have nothing else running in the back of my computer other then the basic anti-virus/anti-spyware programs and some **** like that. With 512 megs of RAM and an optimised Windows XP, I'd expect things to be running a bit smoother...

Anyone as any tips on how I could refit my computer so it could work a bit better?