I put together a new system consisting of:
Ultra XBlaster case
Ultra XFinity 600w PSU
Asus M2n-E SLI motherboard
AMD Athlon 64 X2 5400+ Socket AM2 CPU
2gb Corsair DDR2 TwinX Matched Memory
nVidia GeForce 7600 GS 512mb vid card
Seagate SATA 300 Barracuda hard drive
Everything went together smoothly. I hook up the mouse, keybaord, and monitor and with the tower lying on its side with the cover off I hit the power button. The only thing that happens is, the CPU fan, as well as the case fans, power up BRIEFLY. That is, the system doesn't even come fully on. It powers up for about 1 second then...nothing.
At wits end here. So far, I have a $600 doorstop.