I don't recommend cooler master power supplies. A solid 400W unit should be more than enough - look at these: Corsair VX450, Corsair CX400, Seasonic S12II 430B, Seasonic X400, Silverstone ST45SF, Antec NeoECO 400 & the Antec Earthwatts 430D. I wouldn't waste money on a sound card either, and I'd just get a low end ATI 5000 series card for your audio and video needs.
And I highly recommend going AMD if you are on a budget.