Computer shuts off after 5 seconds, no beeps

ccamwilkins

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Oct 10, 2011
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I've had this computer built now for about 2 weeks. It worked flawlessly for the first week, and then started acting up after that.

When i press the power button, all the lights, fans graphics card, everything, turns on. But no beeps, and it shuts off after about 5 seconds. Then turns itself back on and the process repeats itself...

I have changed the power supply, taken out all components one by one and retried. Reseated the CPU and fan. Cleared the CMOS. Checked the Power switch to make sure it wasn't sticking...

I really don't know what else to try... Please Help
 

rbusch

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Jul 25, 2011
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i had a similar problem once. in my case one of the smaller cables wasnt connected to the motherboard properly. the result? everything shut down after a few seconds because it thought the cpu was overheating. your symptoms sound similat.
 

ordos96

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Nov 3, 2009
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Something is telling it that the CPU is overheating. I have seen this a few times with bad CPU coolers (back in the days of the Pentium D) or improperly installed CPU coolers. There could be other reasons causeing this like mentioned above, but from a logic standpoint, this is whats happening.

Do you see the motherboard logo, or does it shut off before this screen even comes up? Do you have any thermal monitoring (either as part of the case or other parts)?
 

ccamwilkins

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Oct 10, 2011
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Yes, speaker is connected
 

Inferno1217

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Jul 16, 2008
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I had a similar problem and it turned out the CPU somehow was not seated properly and thus began to act up. It eventually would turn on for 5 seconds and shut off. After double and triple check everything else reseat the CPU and reattach the heatsink with some new thermal compound.
 

threefourbeast

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Sep 8, 2011
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I had this issue when I tried to OC my 2600k too far. I think the suspicion of the CPU could be very likely correct.

Can you get into BIOS and set defaults? Flash it if not up-to-date?

Try settings BIOS defaults, then turn computer off, turn PSU off, unplug PSU, wait a little while and then turn it on.