Possible power supply problem

[Onel]

About a week ago, my month-old computer froze up without warning. The power button wouldn't work. Pressing the reset button didn't do anything either. So being the idiot that I am, I reached behind the case and flipped the power supply switch.

When I flipped the power supply back on and tried to turn on the computer, the fans started and the power indicator LED blinked four times in quick succession. Then the computer shut itself off. Nothing appeared on the screen.

I opened the case, and after a little experimentation (read: poking around) I discovered that by applying pressure to the left side of the ATX power connector I was able to make the system boot up. So I put the case back together and thought nothing more of the matter.

Until two days later, when the computer froze up again. Power button wouldn't work. Reset button wouldn't work. So I flipped the power supply switch and repeated the whole process. Only this time, when I pushed down on the connector, sparks flew and I smelled smoke. When I tried to turn the computer on, the power LED lit up and the fans started spinning, but only for one second. I tried shorting the green and black wires on the connector, and the power supply seems to be okay. But when I plug it in to the motherboard, the same thing happens. One-second flash, then nothing. I'm pretty sure I fried a part, but I'm not sure which.

I would really, really appreciate some help. This is driving me crazy.

 

[fainis]

it could be the motherboad that you fried......

 

[Rugger]

Sounds like you had a bad connector on the PSU and have ended up shorting your mobo. I would consider any other parts in the rig to be suspect at this point.

What PSU were you using?

 

[Onel]

It's a generic 480W power supply. There's no branding or anything.

Is there any way to tell if it's just the motherboard that's dead (gasp) or if the processor has been fried to a crisp too (bigger gasp)?

 

[Rugger]

Gotta love generic PSUs... :/

The first thing I would do is get another PSU...a good one. You might as well get another mobo, too. Take out all the other components and visually inspect them for burn marks, scorching, etc, especially around connectors and pins. Use canned air to clean them all and then do another visual inspection. If you or a friend have another rig, then you can test each component individually in the other system. If not, then replace the mobo/PSU, cross your fingers and hope that was the only thing that was fried. Good PSU: FSP 450W for $50.

 

[Guest]

The only "real" way to test these type systems is likely at the manufacturers facility in a one off megabuck test fixture for that particular product, some of the newer stuff just uses jtag ports etc. but good luck running these tests without help from the manufacturer.

The only test method I'm aware of available to mortal citizenship like us is the swap out parts with known working parts in a hopefully somewhat educated sequence. Sounds lame but goes on everyday all day at PC repair shops worldwide.

 

[Onel]

Thanks for the advice, guys. I'll replace the motherboard and PSU over the weekend and we'll see how it goes.