Reading bit more earlier posts..
Just for side info, I run QX9650@4GHz, highly overclocked 9800GX2, 2GB highly overclocked ram, 4 HDD's (one of them is RaptorX), dvd-drive, high-end watercooling, few case fans, three usb devices.
Max power consumption I have seen so far under heavy load is 460W. At stock this idles near 200W and under load bit over 320W.
Just info to let ppl know, you don't need those 1000W psu's until you go for extreme overclocking (liquid nitrogen etc). But when you choose PSU, leave cheap brands out..
They can seriously kill your system. For example you get 500W PSU for 5$, wow whatta deal!!! In real it might not even handle 400W and goes kaboom taking your whole system with it.
QUALITY matters like Jakg has said many times