Friggin' computers!
I have had a bad run lately. After years (decades) of no significant problems.
A few weeks ago one of the wife's computers started acting up, freezes and reboots. I diagnosed that as a bad hard disk. Replaced it with an SSD and restored the OS from a recent image, and all user files from nightly backups via my backup server. Easy (but still a pain to have to do in the first place!)
Next up, wife's second computer (different from the one above) froze up to black screen for some reason unknown. No clean shutdown possible, so went for the "press and hold power button" to force a reboot. No go, after several attempts. Finally had to physically pull the power cord. Then the thing would not power back up. But I could hear a fan running, so there was power to the motherboard - at least at the voltage required by the fan. In initial theory was bad Mobo or power supply. Since it's easier to replace a power supply than the motherboard, I did that. It's not like I don't have a bazillion abandoned computers down in the basement junk pile that are just waiting to donate their parts, including power supplies. After the replacement, computer booted fine. Worked for a few weeks until we had a house-wide power failure. Then it was back to not booting under the control of the power switch, but I could hear that fan running. Thinking about what else it could be besides the Mobo, I thought - maybe it's the power switch itself. So a little jiggling, jostling, and beating on the switch started the computer up again. It's been fine for a week since that. So, still not 100% diagnosed and fixed on this second computer, but I'm currently leaning towards switch rather than mobo. Time will tell which of those it really is (or maybe something else).
And then two days ago, wham! One of MY computers went dead on me. Working fine, then ungraceful shutdown. The first thing I thought was bad memory, since I had just upgraded my memory, doubling the amount installed. But wait, this computer didn't just go wonky or reboot, it completely powered down. That's not typical for bad memory. In addition, when I tried to power it up, all fans would spin up and then it was lights out after 1 second. Even the fans were completely dead. Not enough time for the boot process to even get to memory. Took it outside (since it was full of dust as these things tend to get) and used Dust-Off to clean out the innards. Then checked and reinserted all connectors to the mobo and peripherals, re-seated memory modules, etc. Basically, looking for a short. The thing booted up fine after that. For about 4 hours. Then a sudden "lights out" event again. Dang it. Now I'm thinking power supply. I can't come up with many other events that would result in a power down (as opposed to a freeze or reboot). Not other than a short somewhere or a power supply issue. And this particular computer has a high end power supply in it.
I drug out another old computer, less powerful than my one that just died on me, and installed an antiX frugal instance on it. That only took about five minutes. Then I copied my personal files and settings from MY dead computer over. This copy was done from my backup server - the one that backs up ALL of our computers once every day. So I didn't do the copy from the dead computer (that would have been some feat!), I copied from the backups of the dead computer. So now I'm running - and typing this post - from this temporary replacement computer. I will start debugging my dead computer later today. First step will probably be to replace the power supply. I have plenty of those still available, although none of the caliber that is currently installed in that computer. But it doesn't really need a high end power supply, it's just that this is all I buy these-a-days. My rationale for that was reliability. Ha! I guess I learned my lesson.
With all this recent computer carnage, I am wondering about main line power spikes or something. But all our electronics are on spike prevention devices. Ditto for all our TV's (and any other expensive devices as well). Nothing else has been affected. We have four or five other computers running - as servers and backup systems - and they're all fine. TV's and home theater is fine. Even the much cheaper electronic light switches we have installed are fine (and those kind of electronics go rather fast with power line problems). We rarely have power outages. Maybe once a year for a duration of a few minutes, maybe an hour.
So I'm a bit flustered about the root cause of these recent failures. I hate to blame coincidence. Because I don't believe in coincidence. But until I can come up with a common root cause, I guess I'll be treating each computer failure as an unrelated, isolated and random event.
p.s. - Troubleshooting things like this is usually fun for me. Using my engineering skills. But that is when it is somebody ELSE having the problem. Now that it is ME having the problems, troubleshooting is not as fun as it used to be...
However, I have proven - as has been proven by so many people, so many times before - YOU BETTER HAVE GOOD BACKUPS! I do.