Power Supply Failure???

Ok this should be an easy one for you guys.

One morning I turned off my computer to restart it. Then it shut down normally. I press the power button and nothing happens. No lights or fan noises or anything.

I figured it was my PSU because I can hear this weird high pitched electrical interference noise when I flip the switch on the PSU.

So I pull out the PSU, use a paper clip to connect the power line and a ground line on the mobo connector. The PSU still works. The fan spins and everything. When I connect it back to my comp, it still wont turn on. It seems the fan is really weak when it spins (maybe bceause its not powering a system and there no load on the PSU? idk?)

So what do you guys think it is? Should I blow $130 on a new PSU? or should I blow $600 on a new i7 system. ($600 dollars I dont have.)
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More about power supply failure
  1. Need system specs, including the PSU, to determine what size - and therefore cost - of a replacement PSU.

    Next - troubleshooting boot problems:
    http://www.tomshardware.com/forum/261145-31-read-posting-boot-problems

    The following is a cut 'n paste from a previous post:
    Try to verify (as well as you can) that the PSU works. If you have a multimeter, you can do a rough checkout of a PSU using the "paper clip trick". You plug the bare PSU into the wall. Insert a paper clip into the green wire pin and one of the black wire pins beside it. That's how the case power switch works. It applies a ground to the green wire. Turn on the PSU and the fan should spin up. If it doesn't, the PSU is dead.

    If you have a multimeter, you can check all the outputs. Yellow wires should be 12 volts, red 5 volts, orange 3.3 volts, blue wire -12 volts, purple wire is the 5 volt standby.

    The gray wire is really important. It sends a control signal called something like "PowerOK" from the PSU to the motherboard. It should go from 0 volts to about 5 volts within a half second of pressing the case power switch. If you do not have this signal, your computer will not boot. The tolerances should be +/- 5%. If not, the PSU is bad.

    Unfortunately (yes, there's a "gotcha"), passing all the above does not mean that the PSU is good. It's not being tested under any kind of load.


    Having said all of that, from what you have written so far, you could have a bad PSU. That's why you need to do more troubleshooting.
  2. Well I do not own a multimeter and have no way of borrowing one. So Im not sure.

    My system specs
    AMD 3800+ X2 socket 939
    PSU Ultra 500watt infinity series
    500 GB WD 7200rpm
    7900 GTX 512MB
    4 x 512MB DDR1 Ballistix

    BUT I do want to upgrade soon to i7 cores
    and SLI 275 GTX
    so I was looking at the Ultra 750watt Modular X4 80Plus Series
    This time Im going to register for the lifetime warranty haha
  3. If you know that you are going to upgrade to an i7 core, SLI'd system, a 750 watt PSU is a good place to start. I prefer Corsair, however.
  4. Avoid Ultra if possible (I've had nothing but problems with em, and MSI). Look for at least a 750W from: Antec, BFG, Corsair, PC P&C, OCZ, or Zalman.
  5. I suspect the power supply. If it was your mobo, it would have switched on and off without posting. The fans would have spin and your case leds turned on.
  6. I figured the samething. To broaden my selection Ive looked at:

    Seasonic 750 watt
    $140 - $160
    Seems to get solid reviews
    5 year warranty

    PC P&C silencer 750 watt
    $115 - $150
    Out of stock EVERYwhere :sarcastic:
    5 year warranty

    Ultra X4 750 watt
    $125
    Modular
    Comes with a lifetime warranty

    I'm not sure which one to get.
  7. Jump on the PC P&C ASAP.

    *EDIT* or at least when possible, either the seasonic or pc p&c are better than any ultra product I've had.
  8. Not the Ultra. Either the Seasonic or the PC P&C. And the PC P&C being out of stock simplifies your choice. :)
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