Hi to all the PC gurus on here... I know there's a fair few in the game .

About to build a fairly high end system for my son as follows:

MSI P6N Diamond nVidia nForce 680I SLI Chipset LGA775 with
Quad Core Q6600 CPU, 4GB DDR2-800, 2 x nVidia 8800GT with 512MB on each.

I'm thinking that my spare 450W PSU may not make the grade, is there any formula to go by which would determine what size PSU to go for? I have heard it's possible to hook up a PSU that has TOO much power, is this true? What would be an "ideal" power rating for the above?

Informed replies preferred thanx in advance...

__________________
MY99 WRX sedan WRC blue Sold :(
MY99 WRX sedan Dark blue pearl :D
MY97 Liberty Outback Ltd Wagon
1990 Mk3 Supra turbo fully rebuilt 7M-GTE (Older son)
1991 Celica GT4 (Younger son)