Faulty Power supply?

Hi,

I think I may have a faulty power supply. Coolermaster 700W silent pro

When I have my psu installed, nothing happens when I try push the power on button on my PC (PC1).
I have realized that when I plug in my USB flash drive, the flash drive's LED flashes (dimmed, as if there's not enough power) continuously, non-stop, on/off/on/off at a constant rate. It only stops blinking about 20 seconds after I switch off the mains

However, when I plug in the same flash drive onto another PC that works, it flashes very brightly for about 3 flashes and stops. Windows detects the flash drive and I am able to view files in it. So the flash drive is not faulty.

So I took out the PSU and tried jump starting it by using a paper clip, shorting the green and a black wire. The fans turn on, but I hear a pulsing static crack sound, at the SAME frequency as the LED flash of the flash drive when I plugged it in before.

I am using a spare PSU to power PC1 and it turns on properly.

Specs for PC1: These components are not faulty because they work when I tried it with a different PSU
Core 2 duo e8500
Asrock g41c-gs
No GPU
2x2GB ddr3 Ram

I have also realized that the wattage requirement for PC1 is only about 120W

What is wrong with the PSU? Is it dead?
5 answers Last reply
More about faulty power supply
  1. Sounds like a cap failure in the larger power supply. With a flashlight look for any bulging or leaking caps.
  2. Some USB devices get their power from the +5V rail.

    Your motherboard isn't getting a PWR_OK or Power good signal from the power supply unit so the motherboard won't power on.

    Did you measure the PSU's voltages using a voltmeter to see if they were operating within ATX12V specs?
  3. smorizio said:
    Sounds like a cap failure in the larger power supply. With a flashlight look for any bulging or leaking caps.


    I couldn't see inside properly. All I can see is the heatsink and some copper coils. I notice it is prreetty dusty though

    Anonymous said:
    Some USB devices get their power from the +5V rail.

    Your motherboard isn't getting a PWR_OK or Power good signal from the power supply unit so the motherboard won't power on.

    Did you measure the PSU's voltages using a voltmeter to see if they were operating within ATX12V specs?


    No I don't have a voltmeter :( what else could I do to diagnose it?
  4. If the power supply still has a warranty rma it. If not see If a friend has a spare unit. If not if you have a local micro center they do have a good return police if the power supply not the issue.
  5. Ultra makes a tool to test your power supply for like 14 bucks. Worth having in your tool kit.
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