windows 7 - What piece of hardware has failed?

05
2014-04
  • RJSmith92

    The other day I set some video files converting, around 15 minutes later I noticed that the PC had turned off and the 2 front LEDs were flashing. I turned the power off and restarted it (The GPU made a loud whirring noise as if it had overheated) and everything worked fine until about 1 minute 20 seconds after logging in the display just cuts off. The fans and LEDs are on but no video and holding the power button doesn't turn the PC off, I have to do it at the mains. I tried this a few times and it always cuts off at 1 minute 20 after logging in.

    I have tried -

    • re-installing the GPU drivers (still fails)
    • using a different GPU in the PC (still fails)
    • Using a different hard-drive in the PC (This worked fine)

    I then booted in safe mode and everything works fine. This first led me to believe that it is a software issue, and some driver/service is causing the problem. I then put the hard-drive in another PC and it worked fine.

    I decided that I would just format the drive and install a fresh copy of Windows, the problem is that when it gets to 'Expanding Windows Files' the same thing happens.

    Why would it work in safe mode but not normally?, and I'm really unsure what piece of hardware is causing the issue.

    Any help would be much appreciated,

    Thanks.

    • Answers
  • tbenz9

    I'd bet money this is caused by an under powered or dying Power Supply (PSU). If the PSU is giving unstable voltages or just not enough power it can cause strange symptoms and crashing just as you described.

    Running the computer in safe mode often turns off several features of the OS, which in turn, don't use all the hardware installed. For example, the GPU will not be at full power in safe mode since it's using the basic drivers. These changes can lower a computer power draw and can actually make it more stable on a dying PSU.

    If you have the means, try swapping out the PSU, also, just to be sure, run a Memory test and make sure no errors are reported.

    Good Luck!


    • Related Question

    diagnostic - What would cause a machine not to output a graphics signal?
  • ssg31415926

    I've got a PC which I built myself some time ago. It was working fine. Then we moved house - the PC was moved by the movers. After the move it worked a few times. At one point, it refused to come on (displaying the current symptoms). I flicked the power switch on the PSU and left it to sulk for a day and the next day it booted up. Since then, it hasn't worked at all.

    The current symptoms are as follows. I flick the switch on the PSU and the motherboard light comes on (I don't normally turn it off here but I'm trying to paint a complete picture).

    I turn the monitor on - it goes into standby. Then I press the power button on the front of the PC to power it up and:

    • the fans start running, (cpu, case, graphics card)
    • I can hear the disks spinning, there's a click-click from them but no activity after that - they are quiet models, though,
    • the case has no speaker so I can't hear any beeps (which was never annoying until now),
    • the monitor doesn't come out of standby,
    • the DVD-ROM and DVD writer drawers will both open, when I press the eject buttons.

    If I power the monitor off and on it displays "No signal" on the DVI input (which is the one I'm using), then quickly goes into standby. If I pull the monitor cable out of one DVI port on the card and swap it to the other, it comes out of standby, displays "No signal" and goes back into standby - this happens as I remove the cable and (if I wait for it to go into standby again) as I insert the cable into the other DVI socket.

    If I hold the power button down for 5 seconds or so, it powers off. I'm not sure if this behaviour is a function of the motherboard or the PSU - can anyone enlighten me?

    I interpreted the DVI socket behaviour as meaning that there is some electrical presence on the DVI outputs and so the card might (yeah, I know) be working but has nothing to display. So, I guessed that the motherboard had been physically damaged in the move and thermal shock finished it off after a few runs, and I bought a new motherboard - not quite the same model as before but similar. I'm getting the same behaviour and regretting not coming here first.

    I work with servers - I'm pretty technical - but we have all of our hardware on maintenance contracts so I don't get to play. And, anyway, so much is virtualised these days.

    I'm looking for suggestions to help diagnose the problem, before I shell out any more cash.


    • Related Answers
  • ChrisF

    If the motherboard has integrated graphics you could try removing the graphics card and try to get a signal out of that.

    If that fails then it's most likely that the CPU or motherboard has failed - but without the POST beeps it's virtually impossible to tell.

    Another thing that springs to mind is that you might have a memory failure. Do you have two modules? If so try removing each in turn to see if that affects the behaviour.

    If none of these work it might be worth taking the machine down to a local computer store. They should be happy to help diagnose the problem - after all there might be a sale in it for them!