windows 7 - Computer randomly restarting: motherboard or processor?

  • prolink007

    My computer randomly restarts. Is it more likely my motherboard or processor? So, I know which one to return or replace first.

    • Windows 7 SP1 64-bit
    • Motherboard: Asus P8Z68-V/GEN3
    • CPU: Intel i7

    Times it restarts

    • randomly during use in Windows 7
    • during boot
    • while in BIOS
    • before BIOS
    • basically randomly as soon as I press the power button

    Attempted solutions or diagnostics

    • I have taken the computer down to the bare minimum of hardware components to see if it fixed the problem; CPU, mobo, PSU, 1 memory stick, 1 HDD. The problem still persisted.
    • I swapped all the memory sticks and problem still persisted.
    • I did a memory check on the memory and they seem fine.
    • Nothing is overheating.
    • I tried replacing the PSU with another one that works and it still persisted.
    • Nothing, besides the notice that the system did not shutdown properly, is showing up in the hardware or application logs in Windows.
    • I have reseated everything.
    • I have taken everything out of the computer and cleaned it completely out and still having the issue.
    • I have moved the computer to a different outlet in my house and the problem still persists.
    • I have tried a second working CPU and it still does not work.
    • Checked for blown caps.
    • Swapped out all cables with known working cables.
    • Sent Motherboard for repairs and they repaired it and sent it back and it is still not working

    New Verdict @ 12 August 2013

    I sent the motherboard for repairs to ASUS a few weeks ago. They said something was wrong with it and repaired it and sent it back. However, it is still randomly restarting.

    I did some more part swapping over the weekend and discovered the problem is still the motherboard. I am going to talk to ASUS again today and see what they can do about replacing the motherboard. Will update this post when the problem is resolved.

    UPDATE @ 28 August 2013

    Got the replacement motherboard last night and everything is working fine so far. It has not restarted for 12+ hours. Will be letting it run for the next couple days to see if it restarts. Typically it would have restarted numerous times within the 12 hours. So far so good. =) If it does not restart today or this evening i will create an answer and close this question.

    UPDATE @ 29 August 2013

    Still no restarts with the replacement motherboard. Declaring it fixed.

  • Answers
  • spuder

    Your options are:

    • Remove all but 1 stick of ram
    • Disable sound card, network card, and any other devices in the bios
    • Remove any other PCI devices (video card, sound card, cd rom ect..)

    Once you have done that, and the issue continues:

    • Remove the motherboard from the case. It could be grounding out on a motherboard stand off.
    • Borrow a compatible CPU

    If you have swapped every part, and removed the motherboard from the case, then the only other options are:

    • Bad power cable
    • Bad motherboard

    Just because it came back from RMA, doesn't mean they fixed it.

    Lastly Verify the following:

    If you have a modular power supply, make absolutely sure you use the cables that were provided with it. Modular cables do not have the same pinouts between manufactures.

    Double check that you are using the cables in the right places. I've seen 8 pin power connectors intended for video cards, that fit inside the 4 pin cpu power header. (They are not the same pinout)

    I've seen counterfeit cpu's which are over clocked and are extremely unreliable. (very unlikely)

    Check for blown capacitors. Also unlikely since the board just came back from RMA

  • prolink007


    The solution to this problem seems very weird.

    Here is what i had to do to fix the problem...

    Control Panel -> Power Options -> Change plan settings -> Change advanced power settings -> Power buttons and lid -> power button action.

    Change that setting to "Do Nothing".

    Fixed the problem, have not seen the computer randomly shutdown since the change.

  • Ben Richards

    Perhaps it's the power into your house itself? If both outlets showed the same thing, maybe the power going into your house (or at least on the circuit, if both outlets happen to be on the same power circuit in the house) is fluctuating and your computer is particularly susceptible. If you have a decent UPS (uninterruptable power supply) available to you, try plugging the computer into that.

    A UPS should filter out noise in your power and, if you have any intermittent dropouts in power (brown outs, even), the battery should pick up the slack and prevent the computer from seeing a change in power output. If this is the cause, you should stop seeing the random restarts.

  • Damon

    Disconnect the power button and reset button and see if that fixes it. Start your computer by shorting the power pins with a screwdriver or something without the buttons attached. If it doesn't have the problem any more, focus on the buttons. Based on your description, it is highly likely your power or reset button is mechanically failing.

    If you really want to know if it is your case/buttons, put it all in a new case and see if it still does it.

    CPU and MB issues would be crashes and BSOD's.

  • JohnnyVegas

    If the shutdown is controlled (windows is shutting down etc. messages) then the computer is either being told to shutdown by unknown software or by a faulty power switch. If the shutdown is instant - black screen - straight to bios startup without any messages then I would replace the motherboard for an identical model if possible. Check your event logs for any other clues.

    Try booting into safe mode (push f8 once every second at boot) - When in safe mode, does the computer still switch off on it's own/reboot?

  • Katana314

    This is just one marginal possibility, though after this many answers with no solution, I figured I'd mention it just in case it helps.

    I was seeing this problem myself just after I upgraded to a new video card. The issue turned out to be my power supply - not necessarily that the PSU was 'bad', but because it wasn't ranked highly enough to deliver the power my computer needed.

    Of course, you did mention you had swapped for another PSU. I didn't see any details about whether it was more or less powerful, but if it was around the same amperage, this could be a possibility. However, I would only expect this to be the case if A) You can think of some powerful component of your computer that might be a power hog, not necessarily a video card, or B) Something is using far more power than it should be.

    I think the easiest way to test for that kind of issue would be with a voltometer, if you can get a hold of one.

  • prolink007

    The problem was the motherboard.

    I first sent the motherboard off for repairs. ASUS found a problem with the board and repaired it and sent it back. However, the motherboard was still failing with the repairs.

    I contacted ASUS again and asked for a replacement instead of a repair. They sent me a replacement and so far 36+ hours with no restart with the replacement motherboard.

  • Related Question

    boot - My computer won't start because it keeps restarting
  • portoalet

    My computer suddenly doesn't start today (last used it last week). When start it up, it was up for a few seconds, and then it restarts itself. This happens again and again. There is no beep at all.

    Is this a likely problem with my power supply?

    Edit 1:

    It's the memory module that's causing the problem.

    Booting the machine without any memory module is fine, no restarts happen. But with the memory modules (2x 4GB) on, it just restarts again and again. How can I test if it's a problem with motherboard or with the memory modules?

  • Related Answers
  • Richard

    Is this a likely problem with my power supply?

    That would be the obvious place to start. But could also be HDD (failing on a critical part of the boot code) or RAM (it takes a few seconds to fit the bad part).

    Do a boot to go into the BIOS screens and check this also fails (eliminate HDD, and probably also the RAM), repeat after removing as much hardware as you can—reducing PSU load—to roughly check for PSU issues (this is not perfect, different power rails are dedicated, and if it is the CPU rail at fault you cannot easily reduce the load).