Computer turning on and off and back on on its own ?

xyzWarrior

Honorable
Mar 14, 2013
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10,530
My computer really strange lately. Whenever I restart it, it will turn off, but when it shows the post screen, it will turn back off, all of the fan is turned off, and the lamp on the case is also off, then, without me pressing anything, it will turn on again, then it turn off again. This 'cycle' happens for about 3 times, then it will turn on normally. What could be causing this ? Is it the motherboard, processor, RAM, power supply, or what ? And, sometimes, when I forgot to unplug my USB 3.0 (only USB 3.0, not USB 2.0) device from my CPU, and shut down it, and if I turn it back on, it will take a hell of time ( about 10-15 minutes) to boot. What is causing these ?
My specs are :
i5 2500k not overclocked
700W power supply
AMD HD 7970
RAM 32 GB 1333MHz dual channel
Motherboard GA-P67-UD3-B3
and about 4 fan

Any help will be appreciated.
 

zooted

Distinguished
Feb 17, 2010
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19,360
Silverstone make good psu's, doesn't mean that even quality brands may have issues. I would also booting only with the bare essentials with onboard video and one stick of ram at a time to see if you can narrow it down to a faulty part.
 

xyzWarrior

Honorable
Mar 14, 2013
48
0
10,530


it can boot properly, the problem only happens when I restart my computer, and it also rarely happens.