Broken motherboard or PSU? (Replacement PSU did not fix issue)

Earlier today, one of my computers refused to turn on. I then removed the PSU and tried connecting a different power supply to the mother board to tests to see if a power supply failure was to blame. Once I plugged in the other power supply, the computer was working once more. Afterwards, I used a paper clip to test if the original power supply truly did fail. To my amazement, once I complete the circuit, the original power supply’s fan was running. So what might be the issue might here, a failed power supply or a broken mother board?

In case any back story is needed, this issue originally arose when I plugged in an iPod Nano using a USB cable. After plugging it in, the machine itself beeped for about five seconds until the keyboard's light indicator turned off and the machine itself froze. After that, I tried turning on the computer but it wouldn't turn on.

I would appreciate any help :)
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More about broken motherboard replacement issue
  1. OK. You had a computer failure. You pulled the original PSU and substituted another one. The system worked. The next step should be to replace the original PSU. If the original PSU still does not work, it is bad. It doesn't matter what a paper clip does to it. If it doesn't work in the system, it is bad. This is basic troubleshooting.
  2. fans turning means working psu? um, no.
  3. Went ahead and bought a new PSU to replace the broken one and everything is working fine now. Thanks for the information, jsc. :)
  4. Glad to help.
  5. Okay, looks like replacing the power supply didn't help. After about six hours, the new power supply failed. However, once I reset the CMOS, the power supply starts working again. I reset it once more and tried testing the computer with the older power supply and it's working fine. So there must be an issue with some other than the power supply.
  6. Why do you assume the ps is failing? Check your bios settings. You may have a power saving setting enabled, or the fan on the ps may stop turning until the temp reaches a certain level. My ps fan doesn't always spin, but the system works fine.
  7. o1die said:
    Why do you assume the ps is failing? Check your bios settings. You may have a power saving setting enabled, or the fan on the ps may stop turning until the temp reaches a certain level. My ps fan doesn't always spin, but the system works fine.


    I guess failing is the incorrect term to use in this case. Anyway, I checked the bios settings and I don't appear to have any power saving settings enabled.
  8. At this point, we need system specs, including both PSU's. I agree. Something is going on.

    One thing that could be happening is that you have two PSU's that in your system are marginal. That could explain intermittent failures.

    Speaking as someone with more than 40 years experience in maintaining military electronics, intermittent failures can be very nasty to diagnose.
  9. Computer Specs:
    Intel Dual Core E8400 3.2 Ghz
    ATi Radeon 4850
    Corsair 2GB RAM
    80 GB SATA HDD
    200 GB SATA HDD
    16X DVD-RW

    My original PSU: Antec 500W Earthwatts (Came with case)
    Replacement PSU: Apevia 500W JAVA

    Usually I have these devices plugged in via USB (Other than M/KB):
    Logitech USB Headset
    iPod Nano

    Also, just as a test, I've been running the computer. I haven't done anything hardware intensive, nor do I have anything plugged into the computer other than the basics, and so far it's been running for 6 hours with no issues.
  10. Update: So I plugged in my iPod Nano after having the machine run for six hours straight and it instantly started going through the issues I had previously. First it began beeping, then the mouse and keyboard no longer worked. I tried restarting the system, only to have the PSU not work. After resetting the CMOS again, it worked just fine. Interesting enough, one I plug in the iPod Nano again, the computer works with no issues. It seems as if whenever I plug in an external USB device after a certain amount of time, an issue arises.
  11. nibson said:
    Went ahead and bought a new PSU to replace the broken one and everything is working fine now. Thanks for the information, jsc. :)


    hi this is me Nabaraj Neupane C.E.O of Nibson International Information centre
    an educational consultancy all the way from Nepal.

    my elder son name is also nibson could you send me some of your comments in info@nibson.com.np
  12. nibson said:
    Update: So I plugged in my iPod Nano ...

    Are you plugging it into the case USB ports? If so, try the USB ports on the back of the motherboard. If it works there, you have a problem with the case wiring. And no, I do not know why it would work for a while, then fail. :(

    About the PSU's: the Earthwatts unit is of much higher quality than the Apevia.
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