Check all metal standoff and make sure they are located where it is suppose to be (and not on the wrong hole).
When I connect the power supply to an outlet, the mobo's power led lights up, but when I press the case power button, nothing happens. I have disassembled/re-assembled 3 times; everything is plugged in correctly, but nothing other than the mobo powers up. Here's where it gets a little weird -- with mobo removed from case but with all drives, peripherals, & case switches still connected, the system boots up & runs fine. What am I missing?
Intel P4 3.0E Prescott
Antec Nine Hundred Case
Antec SmartPower 2.0 PSU
Thanks for your help.