Not wanting to trivialize some of the more serious problems being mentioned elsewhere, I'm blessing you all with this brand new thread for me to bitch about computer problems.
** Warning: the following is a largely self-serving rant, albeit with a dash of cautionary tale thrown in, that many will likely not give two shits about.
Things just keep getting better and better.
Hard drive failed several months ago, and I put off fixing it for a while because we have a laptop also. Oh, but the battery in that had also failed so it had to stay plugged in, and not having wireless it needed to stay stationary to get online anyway.
I finally decided to suck it up and buy a nice new hard drive, more RAM, a new OS and a wireless router. We also replaced the laptop battery and bought a new power cord for that after a lightning storm fried the original one.
The desktop was back up and running and I was happy. Considering how cheap storage and RAM is these days, it wasn't much of a cost to restore, and upgrade, its performance.
But for a while it had this annoying tendency to run the fans way too loud and act like a petulant child in refusing to fully come out of sleep mode. So I decided, what the hell, let's take it into a repair shop and see what they can do. I needed to take the old internal HD there anyway to see if they could get the data off it. (No, I did not have a backup.)
Turns out two of the three internal fans were not working properly, were clogged with dust and one was falling apart, there was a fried thermal sensor on the logic board plus other logic board damage. They said I needed to replace the fans and the logic board. Not only would it cost several hundred dollars to fix all this, but given the severity of the issue, despite the fact that the computer was for the moment functioning, not fixing the problem posed its own set of risks not easily brushed aside. (The old HD data, meanwhile, was beyond their powers to restore, meaning another many-hundred-dollars effort at a clean room facility will be necessary.)
The speculation was that the computer had sucked in so much dust (having multiple cats doesn't help) that the fans got clogged, causing them to overwork and overheat, in turn causing logic board damage and likely the dead hard drive.
It all seemed like a shitty, bad-luck situation, a pricey one but, hey, computers break ... until today, when I found something that made me reconsider the timeline and the likely turn of events.
It turns out the fan over-revving happened much earlier than I'd thought -- back when the computer was only a couple months old. Too young to be explained by years of dust accumulation. What I know suspect is that the thermal sensor failed first, perhaps just thanks to that part's typical failure rate, which caused the fan(s) to crank it up to 11 full-time. This in turn sucked in way more dust than would otherwise have been the case. Which clogged up the fans and damaged them. Which caused the internal temperature to rise, damaging the logic board further and killing the hard drive.
The best part? Back when I discovered the fan issue, the unit was still well under warranty. I could have taken it in, had the problem corrected for free, and avoided all this hassle and expense now 3+ years down the road. Goddamn my lazy ass.