[Teisha Nolen]

There are several reasons why the power supply unit (PSU) in your computer may be failing. It could be underpowered; a lightning strike or a power surge could have damaged the unit, and power brown outs can affect the PSU. If the fan is not working or if there is dust in the unit, it could cause a failure. Some of the ways this impacts your system are failure to start up, it could power on and then right back off, memory errors are reported by the system, the system overheats due to an issue with the fan, among other things.
There are a couple of ways to test a PSU. First, you can test with a multimeter. Using a multimeter, you can test the DC voltage of each of the power pins to be sure they are within specification. Second, you could use a power supply tester. By plugging in the ATX 24-pin and ATX 4-pin to the power supply tester, you can review the voltage that way.

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