first time psu troubles - help

[constable]

Last night I think my power supply failed. The PC had been on for about 20 minutes, then out of no where it shut off. No mobo lights, no drive spin, no fans, and it wouldnt turn back on. It was a 2 month old rosewill 400w psu that came with the case.

I picked up a generic PSU from staples (i didnt have time to wait for new egg to ship me one) and installed it. Finally, 5 seconds after I plugged in the power cable from the wall (last) I hear a loud POP. Suprise surprise, my pc doesnt turn on. I took out the psu and i could hear a small object rattling around inside it. The rosewill psu doesnt make that sound.

-the voltage setting was correct
-there was no power switch on the second psu
-there was no power surge, as everything else in the house remained the same, including my roomate's computers.
-all the connections were made to the motherboard and case
-I've only got a single 130gb ide drive, a single dvd/cdr drive, a 16x dx9 graphics card, a wireless network card and three fans (also amd 64 3000 + chaintech vnf3 mobo). I dont think its a very power-hungry system at all and 300w should be well enough rite?

So does this sound like a case of two bad PSUs? Or does it sound like theres a short or something else causeing the psu's to fail? Im kinda apprehensive about going out and buying ANOTHER psu until I get some feedback. The computer worked like a charm for 2 months.

 

[DetroitSportsFan]

First off, I question that your 300 watt generic PSU is enough to run the system properly. You're right, its not particularly power hungry .... but for the most part, generic PSUs are junk.

HOWEVER

The problem you're describing makes me warry of blaming ONLY the psu. I think thats why this has been hanging here several hours without anyone taking a stab. Usually, when a PSU can't run the system properly .... your system becomes unstable, it reboots or shuts off. That "loud pop" is whats scaring me .... I'd be looking at your internals to make sure nothing has shorted or fried. I'd be making sure I didn't reverse any connections. Did you force anything or did it all seem to fit? Most things will only fit one way. It would be one thing for me to fix your computer for you .... I'd put it on the bench and do my troubleshooting and find out for myself whats gone on. Its totally another thing for me to try to predict whats happened based on a few sentences written in your thread. This one's tough because if you don't go through your system carefully looking for signs of shorting or burnt tracks or other problems with the installation and I tell you to buy a new PSU .... you plug it in and IT blows up, you're mad at me.

How comfortable are you with your computer skills? Do you feel comfortable enough to tear it all apart and put it together properly? Because, at this point .... thats what I would be doing. I'd look first for any visible signs of power damage. If it has none, I'd check the parts I could for continuity with a multimeter, Then, I'd test each component separately in a known good system. A surge could have taken more components out.

Maybe now that someone has had enough courage to try to supply you with an answer .... admittedly, not all that helpful (sorry) .... maybe someone else will have the courage to try as well. There's some really good computer people that are regulars on this board. I'm not bad .... but I'd hardly call myself one of the best. Soooooooo .... come on guys! Lets get some ideas posted that may help this gentleman out!

 

[constable]

ahaha thanks for the odd reply. I put the pc together so Im comfortable taking it apart. I can tell you now all the connections are correct and fit perfectly. Im pretty sure the loud pop was the generic psu, because theres now a rattling sound inside it, kind of like when a light-bulb dies.

I exchanged the generic psu for an antec 300w. The results were only slightly different. This time when I flipped the psu's power switch, the whole thing turned on for about 2 seconds then cut off and wouldnt turn back on. I think the antec is still good because when i flip the switch from on to off I hear a faint whine coming from it (the psu, not the drive).

I figured if the mobo really did fail suddenly like that, there would be smoke or a pop or something, but there wasnt. Plus, all the fans and drives turned on for 2 seconds so it cant be shorted. Im considering taking it to a pc repair shop. Normally I would probably take it apart and send the mobo back (its still under warrantee) but I've got way too much pressing schoolwork on this pc to wait for that.

 

[DetroitSportsFan]

Lets start subtracting components then .... one by one ..... to see if you can get the system to run. Now that I know you're not a noob, I'm far more comfortable working this through. An A64 though .... 300 watt psu? Others may tell you differently .... but I honestly feel its under sized ..... even if it is an ANTEC. Yes, I saw your component list .... you're right .... modest components. But that A64 really likes its juice!

 

[constable]

Well, its officially not the psu. I managed to convince one of my roomates to let me test the psu in their pc and it worked. Now im 90% sure its the mobo. :| sonuvabitch