Motherboard: If you're not planning on having more than one GPU, look for a different one.
Hard Drive: No. 300 GB + 10,000 RPM is just...no. You can get a Seagate Barracuda 7200 RPM 1.5 TB HDD for less.
GPU: XFX, no. nonono. Get an EVGA nVidia card (not sure if EVGA does ATi, but XFX is baaaad.)
Sound Card: Are you seriously gonna use this? Why not just use the integrated sound card on the motherboard?
Remember, this is just my opinion on this stuff.