PSU Calculator

Eh, I'd say it's pretty accurate. With the build in my sig an 8800gts, and a couple case fans, the calc gave me ~350w.

I like that they give you options for the chipset, the type of HDD, ect. But the fan selection is a little restrictive, they should have a generic fan option.

Okay I suppose. www.extreme.outervision.com tends to overstate power consumption. However, this one seems to understate my power consumption.

According to this new site, the rig in my signature which has 3 120mm fans, 3 hard drives and 2 DVD Drives uses 229w while gaming.

Here's how I calculate my own power consumption for a typical gaming session when both CPU and GPU are stressed at 100%, but the drives are idle:

12v Rails
E6600 @ 3.0GHz.....................................68w CPU Power Consumption Chart
X1900XT @ Stock Speed........................109w GPU Power Consumption Chart
3 Typical Hard Drives (Idling)..................18w
2 DVD Drives (Idling)..............................12w
3 120mm Fans (assume full speed)........18w

Total Consumption on 12v rails.............225w

3.3v & 5v rails
MSI 975X Platinum Mobo........................30w (Best guess for mobo with some premium features)
2GB of DDR2 RAM v1.9v...........................4w
Audigy 2 Sound card...............................6w
IDE controller PCI card............................6w
3 Typical Hard Drives (Idling)..................3w
2 DVD Drives (Idling)...............................2w

Total Consumption on 3.3v & 5v Rails.....51w

My Total Power Consumption..................276w

PSU Watts And 12V Calculator...............229w

Difference - Under Estimate.....................47w

Its is defiantly a good start. With some work it will be able to rival the Extreme PSU calc(by the virtue of not just calling all HDD's[and other devices] the same, it has some models).