Ok, since Impeller posted this comment as a note, and therefore I see it in my timeline as a regular note, I'll reply here.

I don't know of any manuals for watchdog timers, but it mainly consists of a chip in the motherboard that the OS, or a specific program needs to "ping" from time to time. If the watchdog chip doesn't get a "ping" in the expected amount of time, it powercycles the machine.

I've worked with industrial-grade computers that had those, years ago. In that area they were common. I don't know how desktop computers are in that area nowadays. My guess is that it's still not very common, but maybe if the hardware was designed to be a server, it could have such a chip.

AFAIK, that's what it's called, a watchdog, or watchdog timer.