I personally would go with water cooling because that's probably the best way to go. For an Audio Card I would go with a Creative X-Fi Xtreme Gamer (Name is something like that)
What ever you do, DO NOT get an audigy sound card. They are DEAD Cards and I really have no idea why they sell them still as the driver's for Vista are either completely nonexistent or they are so bad that it's not even worth it to download them.
I would recommend one of these two sound cards if you have the money:
PCI-E 1x -
I have an audigy and I hate it, even though I somehow got it to work after hours of playing around with incompatible software for Vista. When I'm in the market for another sound card, I'm going to be choosing from one of the ones above.
And just to say, ATI video cards have fans on them with insane RPM rates. A 260 GTX at 60% fan speed might be around 900-1300 RPM while a 4870 at 60% is about 1600-1800RPM. I checked the RPM at max speed and found it running close to 3000RPM. Personally, who really needs it that loud and fast?