hey hey hey, dont doubt that card, i have an FX5200 and i can play HL:2 perfectly fine at 1024x768 (no AA or AF or anything though) high textures, high shadows, high everything else. Runs fine, a tad jerky in smoke filled screens but what d'ya expect.
As for the rest of the PC yes, it should all be fine, looks good, although dont go around saying you have 6Ghz CPU, you'll get laughed at, dual core theoretically means you have 2x3.0Ghz but it doesnt quite work like that...
dragon