Heyyo,
I think that vidcard's good enough to crank out some great graphics. me bud has that an an AMD athlon xp 2500 with a gig of generic pc3200 ram, n' he can crank the graphics on full for Far Cry, n' not have to worry aboot frame drops too much. That build should easily be enough to play HL2 np.
Remember folks, he's not looking for state-of-the-art computer, he just wants one that'll get the job done without too much vid lag.
BTW, I have the same mobo, and it works great man. I have no complaints there.
The reason why sfx1999 only scored 54 frames/second is that he cranked the rez (1024*768 ) and I'm also guessing the graphics are cranked to full, and he also has a Geforce 4 TI 4200 (Don't get me wrong, I'm not knocking that card, it's a good card, IMO it's one of nvidia's best cards. I'd rather get that than a fx5600 anyday.
)
Stick with ATI for HL2. HL2 is optimized for ATI cards.