I have a cat and he likes to walk around behind my desk, which is where my PC is. Somewhat frequently (at a rate of several times an hour) while he is doing this, the screen will suddenly turn black and after a few seconds, the fans stop spinning and the computer restarts.
At first I thought he might be jostling cables back there in a way that somehow causes a crash, but I haven't been able to reproduce the problem by wiggling cables myself, and once I started trying to diagnose the problem I quickly noticed that it happens even when he hasn't actually touched the case or anything connected to it. He can trigger it just by walking within a few feet of the case.
I have never observed the computer to crash like this when he's not around. I've been keeping track of when he is and isn't in the room and I always keep programs open on the computer so that I'll know if it has restarted (because they will be gone after a restart) even while I'm away. I was doubting myself at first but at this point I am 100% certain that it really is my cat causing this.
I built the computer early in 2020 and this problem first appeared a couple weeks ago. It is the coldest it's been all winter right now and although I run a humidifier in my room, it's not very effective and the air is still dry enough, and my cat's fur is thick enough, that he seems to be able to build up static merely by existing. So I'm guessing it likely has something to do with static electricity, but I don't understand electricity very well in general so that's as far as I've got. The computer case is sitting on the carpet - theoretically it's sitting on little rubber feet, but in practice those feet sink in and the whole bottom of the case pretty much ends up directly touching the carpet.
I'm asking this question for two reasons: first, I'm extremely curious about what is actually going on here. By what mechanisms can something like this happen? Does this problem suggest I've built the computer wrong somehow, and/or that one of the parts is faulty? Second, I would like my computer to stop crashing all the time when my cat is around. Do I just need a better humidifier? Maybe I should stand the case on something (like a piece of wood?) to electrically insulate it from the carpet and see if that solves the problem? My cat will inevitably rub his face all over the case and all the cables anyway though, so I don't know how much that will help.
Update 1: By sheer luck, I've narrowed down the problem. Today he walked into my room and over to my desk, and right on cue, the computer crashed. However, unlike previous times, this time I was playing a game with music, so I had audio playing. I was able to observe the following sequence:
- The display went blank, then showed a "no signal" message, then went blank again. During this time, the game's audio continued to play as normal, indicating at least the game's audio thread was still running. This took about 5-10 seconds by my estimation.
- The audio began looping, indicating the audio thread had stopped updating its audio buffer for some reason. This went on for about another 5-10 seconds.
- Finally, the computer's fans stopped and the computer began a restart sequence.
As someone suggested, I checked Windows Event Viewer. No system events were logged from during the crash or just before, but there was one from after the restart with the message:
The computer has rebooted from a bugcheck. The bugcheck was: 0x00000116 (0xffffd60fd5a4a460, 0xfffff80617c4bc30, 0xffffffffc0000001, 0x0000000000000003). 0x116 seems to indicate a GPU timeout recovery failure, which is consistent with the observed audio behavior. Looking back in the history, it looks like previous crashes had generated an error with the exact same message (including the same hex constants). So whatever is happening, it's almost certainly to do with the display and/or GPU.