i think that's a great setup. i'd skip on the audio card though...maybe look at getting a set of plantronics dsp500's. you'll love the pci-e graphics.
i've got the same card and its amazing. HL2, farcry, CS: S, etc. all maxed quality settings, all over 100fps.
that hard drive is quite large. i'd maybe suggest getting a 36GB 10k rpm drive for your system then another sata drive, 7200rpm(cheaper) for your audio/video/misc. files.
otherwise great system setup. you should be able to overclock that processor to about 3.6ghz without any problems or having to up the voltage or anything like that.
Sig removed due to size. Please read the rules before adding a compliant sig.