Question Computer intermittently won't come on at all.

Oct 6, 2022
Since about April I've been experiencing an intermittent problem with my two year old PC. One day in April I went to switch the PC on and there was no sign of life at all. I took it to the computer shop and there it came on but the guy there checked all connections and that everything was seated correctly.

The PC then ran faultlessly for the next few months until a few weeks ago where after a power cut it again wouldn't boot. There was power running to it as the external HDD's were spinning up and my headphone lights were coming on when I plugged it in. I opened up the case myself and checked all the cables seemed secure and I reseated the RAM. I also disconnected the power switch from the motherboard and tried jumping the computer by sticking a screwdriver and a pair of tweezers between the contacts. This had no effect.

I put the case back together and left the PC plugged in and occasionally tried the power button. Eventually about 7 or 8 hours after first trying the PC decided to start and ran as normal for a few more days until we had another power cut (these are regular occurrences in South Africa) and again after the power cut it wouldn't come on again. External HDD's were spinning up but no life at all from the PC, no fans, lights, beeps. I waited a day or so hoping once again it would miraculously come back to life again, which it didn't.

I took the PC first to work, thinking it could be possibly my mains power but it also showed no signs of life when I plugged it in at work. Again checked all the internal connections looked secure. I then took it to the PC shop which fortunately is close to my work. They plugged it in and it came on first time, without touching anything other than the power button.

Feeling a bit silly I took it home and again it ran for a day or two until we had another power cut and then it wouldn't come on at all for several days. The periods of it being totally unresponsive seemed to be getting longer. This past Monday I took it into work and the PC shop. This time it didn't come on in the PC shop and the technician said he suspected the power supply which is what I had also been thinking could have been the problem as the PSU is from my previous system and is about 11 years old.

I bought a new PSU and fitted it and my PC was working again. Last night there was a thunderstorm in the area and before it got too close I decided to unplug my PC just to be safe. After the storm was over, I plugged it back in and pressed the power switch and nothing happened. Exactly the same problem I'd been having with the previous PSU. It seems that indeed the PSU wasn't the problem.

The PC still wasn't coming on this morning. External HDD's are still getting power but no action in the tower. It is doubly frustrating because it's an intermittent problem and there's a good chance I could take it back to the PC store and I pay them to check it out again like I did back in April and it decides to come back on so they don't find anything wrong/think they fixed it but didn't.

All of these incidents have been preceded by the mains power being disconnected in some way. Once it comes on and it is continuously connected to the mains, I have no problem turning it off and back on again. Only when the mains power is taken away it seems to trigger whatever the problem is causing my computer not to come on.

This is very frustrating.

Thank you in advance for any help or suggestions.


Welcome to the forums, newcomer!

Can you please pass on the specs to your build like so;

With regards to your above predicament, you'll need to pass on all the parts you'd used to troubleshoot your system/issue.

there was no sign of life at all. I took it to the computer shop and there it came on
It's possible that you're undergoing a grounding issue which might've also ruined your PSU.

the PSU is from my previous system and is about 11 years old
An 11 year old PSU shouldn't even be in any build regardless of how much you've spent on it.