One early videogame that got this right was Alley Cat... in '83!
The x86 version, coded in assembly language, works at the right speed regardless of CPU speed. MobyGames has this to say [1]:
> "Alley Cat was one of the few games of the 1980s that was programmed with full attention to different PC speeds. It's an early, old game--yet it runs perfectly on any machine. The reason it runs on any computer today is, upon loading, the first thing it performs is a mathematical routine to determine the speed of your processor, and as of 2003 we've yet to build an Intel PC too fast to play it."
I had a lot of fun with this game back in the day, when I got my first PC, an XT clone (with Hercules graphics card and "amber" monochrome CRT!).
I had a lot of fun with Alley Cat, Sopwith Camel, digger (https://digger.org/), GW-Basic and Turbo Pascal 3.0 or so when my computer finally got upgraded from a ZX81 (I got it in 1984 as a handmedown from a relative) to an Amstrad PC1512 in 1988 (thanks, supportive parents).
The British truly ruled the low-end computer market in Europe back then.
Lots of love for GW Basic here! It was my first "true" programming language. I started with C64 BASIC but it was too limited to do actual interesting things, at least while not resorting to the cheat of PEEK and POKE.
None of that comes into play in MS-DOS, which never supported multiple processors. CPU 0 on Alder Lake is also a P-core, so you're not going to be throttled by MS-DOS not knowing how to thread-schedule itself. I'm also not certain but would not be surprised if power saving isn't implemented or functional in any of the firmware-provided compatibility SMMs that are running when you boot into such an old OS.
Modern CPUs absolutely do dynamically adjust their speed based on power availabiltity and cooling effectiveness. This is active even before you boot any OS. Now whether or not those CPUs support DOS at all I'm not sure.
The x86 version, coded in assembly language, works at the right speed regardless of CPU speed. MobyGames has this to say [1]:
> "Alley Cat was one of the few games of the 1980s that was programmed with full attention to different PC speeds. It's an early, old game--yet it runs perfectly on any machine. The reason it runs on any computer today is, upon loading, the first thing it performs is a mathematical routine to determine the speed of your processor, and as of 2003 we've yet to build an Intel PC too fast to play it."
I had a lot of fun with this game back in the day, when I got my first PC, an XT clone (with Hercules graphics card and "amber" monochrome CRT!).
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[1] https://www.mobygames.com/game/alley-cat