Well thats depends, firstly which type of games? are u trying big title games like Crysis2, battlefied3, Call of Duty 3? If its anything in that realm just sell/trade up or upgrade your Pc as a whole because the problem you will face wth a high-end GPU and an outdated motherboard and processor (P4 in this case) is an issue of "bottlenecking" which i wont go into now but the short version would be that your board wont be able to fully utilize the power/grunt that a highend GPU has. All good GPU's are spec'd at 2.0 n 2.1 respectively and sure your P4 board's PCI - E (if it has one) is spec'd at 1.0 meaning it will only take advantage of half the power of the card. Since you didn't mention your board, ram, game type' etc i assume you want to run them at max resolution right? My recommendation would be to upgrade your pc's board n processor to minimum Quad-Core and a Radeon 5770 GPU, 4gig ram, 64bit windows.....oh you may need a new PSU. Anyway that's just my opinon from my gaming experince.
