🚀 go-pugleaf

dsmith@bristol.nospam.st.com (Dave Smith) writes:

> Rubbish (sort of).  Device Speed is always a function of temperature, i.e. the
> hotter it is, the slower it runs.  Extra cooling in overclocked machines has two
> functions:
>  o Stop the device from exceeding a safe temperature limit, beyond which the chip
>    can be physically damaged
>  o Keep the device as cool as possible, to maximise the speed at which it can run
>    The colder a device is, the faster it will run.
> 

I'm just back from the pub so restraint mode=unrestrained

Bollocks, the phrase "Device Speed is always a function of
temperature" is wrong. "temperature is a function of device speed" is
correct. CMOS only uses current ( generates heat ) when it switches,
the faster you switch a CMOS circuit the hotter it gets.

The phrase "Stop the device from exceeding a safe temperature limit,
beyond which the chip" is correct.

The phrase "Keep the device as cool as possible, to maximise the speed
at which it can run. The colder a device is, the faster it will run."
is patently untrue. Keeping the temperature will stop the chance of
breakdown by stopping failures due to thermal problems however it will
not stop electrical limits ( capacitance etc. ). If we could cool the
systems enough to make them run fast enough we would be using ZX-81s
in liquid nitrogen clocking at 1GHz. Now there is a thought!

Regards

Robin