Have the game set the defaults for the hardware...this may help.
Also disconnect anything that you do not need (USB, internal HDs not being used for OS or Game) this might get you by for the time being.
Here is a little bit of info i had found:
6. Minimum of 500-600W Power Supply with a minimum of +12V @ 30A for all PC components in SLI mode
the System requirements are at the bottom of the page.
http://www.cdrinfo.com/Sections/Revi...rticleId=19211