Random power outages

I have an intermittent power issue and am trying to work out the most likely culprit, so I can swap that out, then move to the next etc.

Occasionally, maybe 1 time in 20, I turn the PC on at the wall socket, and nothing lights up. It's dead. I switch off the wall socket, wait a bit, turn it on and it does light up and will boot as normal. Sometimes I have to do this a couple of times.
In use, also occasionally, the monitor screen will briefly (no more than a second) go black, and then come on again.
Previously I've had a problem where the PC's Bluetooth didn't initialise so keyboard etc wouldn't connect - restarting the PC fixed it - but haven't had that problem for some time so some update may have fixed this.

It seems to me like for some reason the power occasionally isn't getting to components. Do you think this is most likely a motherboard or PSU issue? (Or I suppose it could be the wall socket or surge protector extension lead that everything is plugged into.) I've not overclocked anything.

What's your best guess for where to start in swapping things out?

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What I'd do first is if the wall socket has two ports plug a lamp into the other one or get a 3-in-1 plug, make sure power is continuously available to it, could be an issue back to the circuit breaker panel. If that checks good, change the cord from the wall socket to the computer. When I got frequent short power bumps some years ago I ended up getting a UPS/Uninterruptible Power Supply to prevent the computer being shut down, includes the Surge Protector feature. The UPS holds power for 10 to 30 minutes after the commercial power is off, main feature is to prevent loss of data, provide time for an orderly save and shut down.

This sounds like a PSU issue to me, rather than a wall socket problem, though it is good to check that too.

Do you have a PSU that you can borrow to see if that is the cause? Also, make sure that all of your PSU connections are solid on the motherboard and that they haven't come loose.

Just as an aside, I had a PC at work that was finicky starting up. Turns out it was the soft-on power switch on the front of the case. I changed that out and no more problems.

There may be a problem with the power button.

ricardomax said:

In use, also occasionally, the monitor screen will briefly (no more than a second) go black, and then come on again.

Click to expand...

Video signal is being lost. For example, when switching refresh rates (e.g. in games) or poor connection.