My graphics card wont even play Halo, I don't think it will play HL2. and i have never played them before, so i wanted to see what it was like. And, Pimp, this copy wasn't the used one. I really didn't trust the $12 used one to work. this was $30 at Wal-Mart. but i fixed it. it turns out that it wasn't a compatability issue with XP, it was a problem that I easily fixed with a few short commands in the command prompt. it was a "16 bit subsystem" error. if anyone has this problem, go to microsoft.com and look it up, it really works. and it was just as simple as copying and pasting the commands. but its worth it. I could have played Blue Shift, and Opposing Forces, but i wanted to play the origional. anyway, mods, you can close this thread. Hey, someone IM me if they wanna play Counterstrike when i get home. I get really bored,so that would rule. thanks.