Yes, it was called the PC Speaker, and that's pretty much exactly what it was used for. https://en.wikipedia.org/wiki/PC_speaker
It was standard equipment through the (mid?) 90s, and completely independent of the (optional) PCM sound card.
Now PCM sound is built in to motherboards and the PC Speaker long ago faded into irrelevance. Modern motherboards don't even have headers to connect a PC Speaker. Some motherboards will emulate the PC Speaker over the built in sound output, but of course you need speakers plugged in and on to hear those beeps.
Often just minutes if you're running them near their rated power. Conventional UPSs are generally designed to power your devices just long enough to shut down your computer "safely" [1] or to start a generator. They advertise power ratings but typically not battery capacity at all, and that's because it sucks.
2026 update: don't buy a (conventional, lead-acid battery) UPS. Buy a LifePo4 power station instead. They're actually designed to keep your devices running for hours without main power. They used to not fail over quickly enough to avoid a typical machine going down (briefly), but now they commonly advertise 10ms to 20ms switchover. Also, you don't need to replace the batteries nearly as often. Like, once every 10 years instead of once every 3 years. And the price has really fallen recently. LifePo4 is (unlike some other lithium ions) known as a particularly safe chemistry, so you don't have to worry about fire risk.
[1] This matters if you have crappy software and/or hardware that loses data if shut down uncleanly. If you use modern SSD/HDDs that flush their write caches when asked to, modern journaled filesystems at their default settings, and modern databases like SQLite or PostgreSQL at their default settings, you should be fine just pulling the power plug any time you feel like it.
But glad to see 'slapping AI buzzwords on top of your article to get more views' has been a thing since 2023.
Also cheers for the PSA, I don't think the draw is something I'd considered when using my ups.
If it's misleading, it's because the cat debugged the computer's power supply issue, not stable diffusion per se.
Correct title.