I've got a pair of those bad boys. If I leave the case open I can hear them over all the fans. I sprayed some dynamat on the inside of my case and I can hardly hear them now.
Overclocking is like supercharging. It's not necessary, but it sure is fun to have the fastest in town!!
Stock cooling(until I get a water block)
1GB PC3200 OCZ Gold EL(2-2-2-8-2 1T 5:6 Divider)
Sapphire X800GTO2(520/580 - Unlocked 16 Pipes)
Antec TruePower 550 vmodded
2x Western Digital WD-1200JS(RAID0)
Lite-ON 1633S DVDRW