How much power do I need!! Help!

Greetings:
After two trips back to the factory for repair of my motherboard( 1 year old) to replace the PCI-E slots I still cannot run an ATI 4580 crossfire video card. It keeps telling me the power supply is not connected. It is not the card because this is the third card and none of them work! ATI says that the minimum power required is 600 watts with I think (can't remember) about 25-30 amps.Is it possible for one rail to go bad while the rest of the PSU functions normally? If that is really what the problem is? At this point I am at a total loss of ideas.
So why won't this thing work? help what am I missing???



ASUS M4A78T-E PCI-E 2.0 MOBO
AMD Phenom II x4 CPU
2 gigs Corsair Extreme ram
2 SATA HDDs
Ultra4 Modular 600 Watt power supply with dedicated 12v rail supplying 37amps
WinXP Pro Service pack 3