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Comment by taneq | Hacker News Reader

Similar issues (calculating somethings-per-second when the test 'something' started executing faster than expected) caused a good number of games to stop working as CPU speeds increased.

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Same for GPUs and actually still happens with many games that use delta timing (meaning they calculate the time delta between the last frame and the current frame and use it to update the game world state). For example in Condemned you often get stuck for a few frames to random junk/pebbles/etc on the floor (and the game has a lot of that) if the game runs too fast. Other games have issues like collisions not registering, jump distances being too long/short, etc.

Because of that i always run any games that are more than 5-6 years old with a frame capping tool.

I imagine the purpose of the turbo button on some PCs was to mitigate this effect https://en.wikipedia.org/wiki/Turbo_button

That's precisely what it was for! In the era just before said games which would attempt to calibrate their delay loops against the realtime clock, games were only expected to run on a single speed of CPU and used hard coded delay loops to achieve their desired speeds. When someone got a new computer that ran twice as fast, the game ran twice as fast too. So as a stopgap, they gave you a button which underclocked your fancy new 386SX from 20MHz to 12MHz or whatever.

(In looking up the clock speeds since it's been that long, I also learned that some 386 chips had bodgy 32-bit multiply logic and were sold as "16 bit", and due to the weird way humans assign value, apparently these are now valuable collectibles! Source: https://en.wikipedia.org/wiki/Intel_80386#Early_problems)

And the turbo button created its own support calls back in the day: "My computer suddenly seems very slow." "Try pressing the Turbo button." "Thanks, that fixed it!"

Sometimes you also needed to switch L1 and/or L2 cache off to get correct speed in addition to pressing turbo button.

If you were unlucky, underclocking was the only option to get the speed just right. Not fun in the era when clock speed was set with mainboard jumpers...

Of course there were also TSR [0] utilities to slow down old games.

I remember twiddling with all that to get some early XT era games working properly. Computers were getting faster so quickly that you'd literally see a new faster model for sale in as little as 1-2 months later. Slowing down things just right amount was an art form in the mid to late nineties.

[0]: TSR: https://en.wikipedia.org/wiki/Terminate_and_stay_resident_pr...

> Computers were getting faster so quickly that you'd literally see a new faster model for sale in as little as 1-2 months later

It was crazy. If you didn't buy a new CPU just about every year you were woefully behind.

The last two CPU generations I bought made it almost 5 years, and frankly there wasn't much difference from upgrading.

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