thats not really what you’d call a gamers card, I’d suggest going with something quite a bit quicker (unfortunately quite a bit more expensive also) -
ATI: 9500pro, 9600pro, 9600XT, 9700 (non pro, pro), 9800 (non pro, pro, XT)
nvidia: 5600Ultra, 5700Ultra, 5900, 5900Ultra, 5950Ultra
(later models preffered but more expensive).
Bear in mind DOOM3 and HL2 arent expected for like 4-6months! Unless you need a new card now then IMO it makes sense to wait, youll only get a faster card for your money.
there’s a variety of dedicated computer hardware sites to help you make your choice, http://www.anandtech.com/video/index.html & http://www.digit-life.com/ are just two.