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General => General Technical Chat => Topic started by: paul_g_787 on June 15, 2021, 03:14:07 pm

Title: PC Powering Off - Strange Issue
Post by: paul_g_787 on June 15, 2021, 03:14:07 pm
Hi everyone. Thought you all might like a laugh so I will share what just happened to me.

My PC is a custom build one I made in 2012 and have upgraded the odd parts since, but still the same case, psu and m/b it has always had. So it is a few years old now. I currently run Ubuntu 20.04.

The last few days I would come into the room and my PC would be off. I turn it on and it is fine.

Today I have been working for a few hours and I found out that it kept popping up with the shutdown prompt (as if you pressed the button) and it would shut down after 60s unless you clicked cancel.

So I took it apart, cleaned all the dust out, re-seated everything and it worked great for about 3 hours. Then the prompt came up again, then again after 5 mins, then again and again!!!!  |O

I first thought overheating but all my sensors were reading fine. Rather bamboozled at this point.  :-//

So I had a look at syslog and it said that the acpi power button kept being pressed?????? It felt fine to me mechanically.

So I next popped of the side panel and disconnected the power switch from the header. The problem went away! Yes!!! Connected it back up and the problem came back. So great I know it is a hardware issue...

So I removed the switch from the case (panel mount type) and had a visual inspection, the wire isn't damaged at all and no physical damage to the switch. Hooked it to the multimeter in continuity/diode (beepy) mode and it is working fine. But then if I left it on the table the meter would occasionally read continuity..???? How strange.

So at this point I thought perhaps there is some conductive foreign material somehow inside the switch?

I managed to un-clip the casing of the button and to my surprise there is a hecking-chonky cheesy bug living in the power switch!!!!!!!

The strangest thing is, the only hole in the switch is a 0.8x2mm hole in the bottom. I did not know cheesy bugs could get through such small holes!! Maybe he grew up his whole life in my power button??

There is no corrosion or any foreign material inside the power button, so I can only guess the little bastard was pressing the contacts together to annoy me. (And it has worked).

So I cleaned it out with some switch cleaner/lubricant for good measure and put it all back together. The PC is now working fine for over 2 hours so far!

The cheesy bug now currently is residing on the bird table in the garden. (Serves him right).

Now maybe I can actually get some work done today.. Wish me luck!
Title: Re: PC Powering Off - Strange Issue
Post by: David Hess on June 15, 2021, 05:41:25 pm
So you literally "debugged" your computer.
Title: Re: PC Powering Off - Strange Issue
Post by: paul_g_787 on June 15, 2021, 07:23:11 pm
So you literally "debugged" your computer.

Exactly! :)
Title: Re: PC Powering Off - Strange Issue
Post by: james_s on June 15, 2021, 08:13:44 pm
Well that's the first time I've ever seen that happen. Must have got in there as larva and then grown. Ick.
Title: Re: PC Powering Off - Strange Issue
Post by: paul_g_787 on June 16, 2021, 04:18:35 pm
My PC is working fine today at least.

This is my second buggy encounter in electronics.

The other being a rather crispy spider between the anode and kathode of the ECC83 of my Marshall Bass amp causing it to hum.