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Yesterday when I turned on my PC the fans began to spin as usual but my monitor did not display anything. I tried various troubleshooting techniques (including trying a different screen and cable) but to no avail. When I woke up this morning to continue the troubleshooting process the computer will not even turn on. Upon pressing the button absolutely nothing happens. I have tried reseating all my components but this does not seem to have solved it either. It's worth noting that the night before I began experiencing these issues, when shutting down I removed the power cord from the PSU instead of shutting down the PC conventionally. I don't know if that could have caused this somehow.

I have noticed however that after about 20 seconds of plugging the power cord in, it turns on for a split second (the fans begin to spin and I see lights on the motherboard, but probably for only a tenth of a second).

Does anybody have any ideas of what could be wrong? My best guess at the moment would be the PSU, as over the last few weeks the fan wouldn't spin, and I would have to restart for it to start spinning. I can also hear a feint high pitched sound when I plug the power cord into the power supply, however I'm not sure whether this sound was present or not when the computer was functioning correctly.

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up vote 4 down vote accepted

It's worth noting that the night before I began experiencing these issues, when shutting down I removed the power cord from the PSU instead of shutting down the PC conventionally.

Do you mean that you just pulled out the power cord while the computer was turned on?

If so then there's a good chance that you've damaged some of the components. It could be the power supply, the CPU or even the motherboard itself.

From the description you've given it would suggest the PSU.

Have you noticed any electrical burning smells?

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Yes, unfortunately I did pull out the cord while the computer was on. Now that you mention it, a few days ago when the computer was still working properly I did notice a slight burning smell. It seems I had left my PC running for a while without realising the PSU fan wasn't spinning so it had gotten very very hot. I shut down for about 10 minutes and upon restarting everything seemed fine (and the fan started spinning again), so I honestly didn't think much of it. – Post Feb 22 '10 at 14:18
@Post - sounds like the PSU is fried. – ChrisF Feb 22 '10 at 14:23

If i am not to wrong i have had the same problem.

Your PSU is defect. that simple. (if it is the same problem i had)

Try to borrow a PSU from a friend of a local shop that is helpfull.

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You mention that the PSU has been faulty over the past few weeks, do you have another PSU that you would be able to test the system with? I know its a longshot that you do but worth a try.

Back to your original point do you use a graphics card or the onboard graphics module? If you use a graphics card it might be worthwhile removing it and testing if the onboard vga output works.

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Unfortunately I don't have on at hand to test. I do use a graphics card, and when the computer was actually turning on while I was troubleshooting the graphics issue, I did try without the graphics card in and even with my old GPU, but still no result. – Post Feb 22 '10 at 14:23

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