I am new to working on computers, and I have an eMachines T2895 2.8 Celeron D, 512DDR that fried the mobo. I got a replacement mobo and installed it. It booted up and ran fine but after 3 times hitting the power switch. After I shut it down, it will not boot now. When you press the power switch, the led will light but then the computer will immediately lose power. Then nothing if you press the power switch again (unless I unplug and replug the computer in). Sometimes the fan and LED will stay on for about 5 seconds before losing power. What could be causing this? Power supply? power switch?

WHat was it that fried your first mobo? if it was a faulty power supply and you didnt replace it guess what is going to happen to your new mobo?

I have no answers, but I have an eMachines W1640 that I just replaced the power supply on. It wouldn't boot for anything. Finally did and now it runs fine...as long as I don't shut the power off. Reboots; shuts down; boots again from the front panel switch - as long as the power isnt turned off.

To boot from cold, I must
1) remove the HD power and data cables.
2) Hold in the front panel switch
3) Turn on the back power switch
4) usually wiggle the front power switch.

Once the mobo boots, I can plug the hard drive back in and things run fine!

And yes, I've tried a different switch!!

wow... that is a problem alright

The answer is a bigger power supply. 300W - instead of the 250 the tech's recommend - does the job. Silly engineers.

My PC did that before i fried my last processor. It would whirr a bit, and then just turn off. Might be worth checking that your cpu is ok