Why Did the Turbo Button Slow Down Your PC in the '90s?
howtogeek.com
5 threads
Or the button sped it up.
The female connector on the button was directionless; motherboards provide a two pin header, and the typical local PC builder would hook it up arbitrarily based on what they thought was correct or what was easier in the assembly.
On some old XT clones the turbo button did nothing, but Ctrl+Alt+Num- did the trick :D
I liked to flip the button around and have turbo on = faster, turbo off = slower.
Site blocks Tor.