As far as I understand, it’s purely marketing semantics.
The point of the ‘Turbo’ button is to slow the CPU down to provide compatibility with old software that was written with a fixed clockspeed, where the software would become unusably fast on newer CPUs.
Calling this a “slow” mode or “compatibility” mode wasn’t very marketing-sexy however, so manufacturers just flipped it around and called the normal speed ‘Turbo’.
With later systems, developers all became aware that varying CPU frequencies were a thing, and started to base their software timings on the realtime clock instead.
So in later systems there was no longer any need to have the CPU run at anything other than its maximum (normal) speed - and the turbo button simply went away.
As far as I understand, it’s purely marketing semantics.
The point of the ‘Turbo’ button is to slow the CPU down to provide compatibility with old software that was written with a fixed clockspeed, where the software would become unusably fast on newer CPUs.
Calling this a “slow” mode or “compatibility” mode wasn’t very marketing-sexy however, so manufacturers just flipped it around and called the normal speed ‘Turbo’.
With later systems, developers all became aware that varying CPU frequencies were a thing, and started to base their software timings on the realtime clock instead.
So in later systems there was no longer any need to have the CPU run at anything other than its maximum (normal) speed - and the turbo button simply went away.
…we had finally achieved permanent turbo.