I was given an E-Machine with a ASUS motherboard (P4S533-MX). The computer will not power up and the green stand by light is on as long as the cord is plugged in. I tried clearing the CMOS. I put a new tested power supply and unplugged the CD Rom. Only the hard drive and two sticks of ram, mouse and keyboard are hooked to the motherboard. The off/on switch works. And the monitor is good. Any ideas. RPM

How did you test the on/off switch? They're usually off/mom-on switches, did you hook it up to a meter and make sure that's how it's functioning? What about directly jumpering the power-on pins on the appropriate header on the MoBo? Does the fan start to spin up or anything when you press the button or jumper the pins? Inspect for swollen capacitors, obviously fried ICs, burnt off traces, etc.? Standby light being on all the time is pretty much standard fare if there's juice running to the board but it's not turned on.