> You didn't do the experiment I suggested:
>
> Run a 200MHz-rated CPU at 75/100MHz, and a 75/100MHz-rated CPU at 200MHz.
I think Intel chips are speced for 50-100% of their rated speed.
i.e. you're allowed to run a 200MHz CPU at 100MHz if you want too.
On the other hand, they will NOT blow up at lower speeds. Clock
multiplying may become unreliable at lower speeds, but at a multiplier
of 1, that too should be OK.
Next, many motherboards do a "divide clock by 32 when in powersave mode",
so the motherboard manufacturers seem to think that this won't harm
processors. (They most likely don't adapt the multiplier either, so
I guess that must be working too....)
In the old days, Z80's were speced 100khz - 1MHz. You could run them
at 1Hz, and probe the (live) bus with a led...... Or single (*) step them
with a simple button.....
Roger.
(*) Well, a bounce (**) of the button would occasionally forward the
chip more than one cycle....
(**) Those are usually "ms" range events.