Woops forgot to mention Enemy Territory is an online based first person shooter like counterstrike, for those that didnt know.

O.k heres a totally addictive game that runs very well on my 1.9ghz sempron cpu 521mb ram nvidea geforce 5500fx graphics card and windows XP It's Wolfenstein Enemy Territory. The graphics are nowhere near staining the graphics card. It hardly ever lags is well but the lag is based on your internet connection(I think), but this game runs without a hitch on my system and it's free to download and free to play. I highly recommend, but I would say that cus i'm a big fan of the game.