Thank you so much guys. I've got a couple more questions, if you don't mind.
1) Is it worth buying 9600GT or 8800GT or even 8800GTS over my current card (x1900xt)? If so, how much improvement should I expect in new games (FEAR, Oblivion, NFS Prostreet, COD4, TF2, COH, and upcoming ones...)...