PC wouldn't post and now it's suddenly working again, what's wrong?

SpartanSpurs

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Dec 24, 2012
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For a few months I had a problem of my PC randomly rebooting during games and yesterday I decided to overclock my i5 2500k back to 4.2ghz because I'd reset the bios to try and fix the problem. However after that my PC rebooted, but never posted and kept rebooting but it wasn't getting anywhere so I just turned it off. I then bench tested it and all the fans would run when it turned on, including the PSU fan, but that was it. I then plugged in the internal speaker and it gave off continuous short beeps, meaning a power error. So after that I reserved PSU to pick up today and stopped for the evening and decided I'd check everything again tomorrow.

So this morning I decided to test the PSU on an old motherboard and CPU I had lying around and it worked, to my annoyance that is, because that would have meant I had another problem. It even worked when I plugged in my 660 and told me I needed to insert a system disc.
So on the off chance of a miracle I plugged my PSU into my current motherboard and it started too. I'm now completely stumped. I've left it in pieces because I'm worried whatever part is dodgey may kill the rest.

So my question is, what is wrong? However as it's "working" again, I obviously can't perform any more tests.

Oh and just some spec if it helps: i5 2500k, Gigabyte z68ma-d2h-b3, Mushkin 500w volta, Corsair H60, a GTX 660 and Muskin blackline ram.
 

SpartanSpurs

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Dec 24, 2012
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Sorry, I forgot to add I tried it with a different CPU as well. It was a 775 board so my 2500k didn't fit.
 

James H

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Jun 15, 2013
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As a speculative guess...if its generally happening while gaming then I'd say look at the GPU, perhaps its a dodgey connection on the mobo or perhaps its the GPU itself, because as you run games the GPU is under stress and could give up, which is why your only seeing problems while gaming. Hopefully someone else posts with more experience :)