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I have a PC which I can no longer turn on. That is, I press the power button and nothing happens, not even the CPU fan starts spinning.

I have tried removing all but the most essential components (so only leaving the PSU, motherboard, CPU and RAM), and this did not make a difference. I'm suspecting it is the PSU, however as long as a power cable is connected the LED on the motherboard does emit light.

I have tried connecting a different motherboard/CPU, and this did not make a difference. Is it safe to connect the PSU to my regular PC to see if it works? We have had two power outages recently, so I'm worried that the PSU might be sufficiently broken to cause a short when used with other (currently working) hardware. Is that even possible?

Also, my friend suggested it might just be the power button that's broken - I tested this theory by connecting the two motherboard pins using a metal object (screwdriver), and nothing happened. I am assuming that's a correct way to test that?

Thanks in advance for any advice.

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From what it sounds like to me, and the given troubleshooting path you have taken, the power supply is probably not working properly. While it is true that the LED light on the motherboard lights up, that doesn't mean that the PSU is fully operational.

Suggested Step:

  • Test a known GOOD PSU in the suspect machine, to see if it works or not. This will tell you if the issue is the PSU or perhaps the motherboard causing the issue.

Having an unprotected computer, not on a power surge protector, can wreak havoc on your PSU and system, so in the future, make sure that you protect your devices with a good surge protector.

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