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Computer doesn't turn on consistently

  1. May 19, 2016 #1
    I have a situation.

    One of the computers I work with (desktop, early 2000's gateway) doesn't turn on anymore.

    The last time it was working was 3 hours prior to when I began working with it. The power button was flashing, showing hibernation. The screen was off. I moved the mouse and nothing happened, so I pressed the power button once. The hard drive started spinning as expected but then the computer strangely shut itself off instead of turning back on. Afterwards, I pressed the power button a few times but it just doesn't turn on.

    I looked at the back of the computer at its ethernet input/output. It is still flashing.

    What could be the source of the problem?
     
  2. jcsd
  3. May 19, 2016 #2
    Possibly the motherboard.
     
  4. May 19, 2016 #3
    If the lights are flashing, it sounds like the system is in suspended mode.

    Do this. Click and Hold your power button for 5-8 seconds. This does a hard shutdown on the system. This will ensure that the system is completely off. Then pull the power cable out of your system, then push the power button again for 5 seconds, this is to ensure that all the capacitors are drained. Then plug the power back into your computer and try to turn the computer back on.

    Let us know what happens.
     
  5. May 19, 2016 #4

    SteamKing

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    It could be a faulty switch. Or it could be the CMOS battery.

    I have an old home-built system which I put together in 2007. As my system got older, I noticed behavior similar to what you are experiencing with your Gateway: after I got the system booted up, it would work a while and them shut down mysteriously. After doing a little troubleshooting, I concluded that the battery on my motherboard was not maintaining a sufficient current to keep the system working like it should. This battery is one of those flat ones which looks like a quarter (a CR2032 is a common type), and it's supposed to keep the real time clock working when the machine is shut down among other things. These batteries are also supposed to keep your motherboard's BIOS memory intact while the system is off, and if the battery goes bad, your system BIOS settings could be corrupted of the BIOS is put into a continual reset state, which prevents the system from starting normally.

    I recommend examining your system to see what sort of CMOS battery it has and then replacing it. A CR2032 costs two or three dollars at most drug stores or electronic shops (these batteries are also used in watches and other electronic devices). When I replaced my old CMOS battery with a new one, all of the strange behavior my old system was exhibiting went away.
     
  6. May 19, 2016 #5
    Thanks guys. I tried the turn off, drain capacitor procedure, didn't work. I had a colleague help me with it and it turns out the power source was broken, so a new one is being brought in.
     
  7. May 19, 2016 #6

    SteamKing

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    That works, too. Power supplies are subject to failure, particularly if you live in an area which is prone to having thunderstorms or other power interruptions.
     
  8. May 23, 2016 #7

    CWatters

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    Electrolytic capacitors used in power supplies have a relatively short design life. This can be dramatically reduced if they are operated a bit too hot. If the PC is from the early 2000's then it could be 15 years old so it's done quite well.
     
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