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PC won't turn on. Fans spin for half a second and then turn off.

Last night I turned my pc off like I usually do except this time I flipped the switch on the back of the PSU because I wanted to save power because when the PC is just shut down (usually) the LED's are still on. When I woke up this morning I went to my PC and flipped the PSU switch into the on position and then pressed the power button on the case. The fans turned on for about half a second and then turned off again. Same with the LED's. Did I break my PSU somehow? Please help
6 answers Last reply Best Answer
More about turn fans spin half turn
  1. Open up your case and check everything from the PSU is still connected to the board and your components. Sounds like the CPU cable from the PSU is loose.
  2. JimmoR3M said:
    Open up your case and check everything from the PSU is still connected to the board and your components. Sounds like the CPU cable from the PSU is loose.


    The CPU power cable was the first thing I checked. Everything is still wired up.
  3. Best answer
    Isolate everything, first try to replug all wires from the psu to your mobo, and try to clean the gold parts of your RAM.
  4. i have had this problem before, a couple of times... it could be that something has worked itself loose, hopefully it is as simple as that. But it is more likely either your psu or motherboard that has gone. a power surge could do it, even though your psu was off, a surge can still come through your ethernet cable.

    you can do a quick test on your psu, called the paperclip test (google it) to see if it is still working (although the test is by no means definitive, your psu may still be faulty even if it passes the test), if you can get your hands on a one that you know works, that would be first prize.
    next is to take out the components one by one to see if any of them may be the culprit.

    the motherboard is the most difficult to check, unfortunately it is also a prime suspect... short of swapping it with a spare if you have one... you may have to take it in to pc repair shop, otherwise you may just have to purchase a replacement.
  5. Do you hear a simple click from the PSU before it powers down? If so unplug everything and do the paperclip test, the same thing happened to me this past monday and it was my PSU being dead. Hit power button, fans spin up, fans power down, all within maybe 2-3 seconds. PSU is most likley dead, use the warranty and RMA it.
  6. Taking out the CPU power cable and the motherboard power cable and putting them back in fixed the problem. Thanks
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