system powerup problem, please help

[wxiao]

My PC died a couple of weeks ago. My first guess was that the PSU is dead. But using the a paper clip, I was able to power the PSU up. My next suspect was the motherboard. I installed a new motherboard today. Still no luck. With the 12v ASX connector of PSU inserted onto the motherboard, I can even power up the system by inserting the paper clip into the 24 pin power connector of the PSU. But when I pressed the normal power button, nothing happens. So my next guess is that the power button of the case is faulty. So I tried to short the two "power-on" pins on the motherboard to boot up the system, no luck.

I am out of ideas now. Any opinions?

 

[NesuD]

I would go back to the power supply. The paperclip trick doesn't always tell the whole story. Best test is a genuine power supply tester around $20 bucks or a known good power supply to eliminate that as the problem for certain.

 

[wxiao]

I would go back to the power supply. The paperclip trick doesn't always tell the whole story. Best test is a genuine power supply tester around $20 bucks or a known good power supply to eliminate that as the problem for certain.

I noticed something weird about the PSU: when the power cord is plugged in, and the PSU is NOT plugged into the motherboard, the PSU green LED is on. Immediately after the PSU is connected to the motherboard, the LED goes off. Is this normal? Any indications of the kind of problems it has? Thanks.