[vox-tech] underclocking

[Jeff Newmiller]

On Sat, 5 Jan 2002, Ryan wrote:

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> This got me thinking, my firewall has a pentium 120, does this really need a 
> fan?

The 486DX2-66 had overheating problems when it first came out.

I think the answer is specific to each chip, because they lowered the cpu
voltage as they climbed the clock speed ladder, but they didn't do it in
step with the clock speed increases.  There were other things they did to
handle the thermal load as well.

Finally, firewalls typically have a very very low cpu load.  Put a
computationally intensive application on that cpu and the temperature can
rise by 20 degrees C.  Run a pppoe connection and start pumping data
through it and watch your cpu temperature rise.

Learn by trial and error.  Older cpus didn't have built in temperature
monitors, so it was harder to experiment with them.... you had to wait
until the cpu locked up.  External temperature monitoring is not likely to
be helpful, unfortunately.

> 
> On Saturday, January 05 2002 09:21 am, Peter Jay Salzman wrote:
> > henry, my firewall, mephisto, is using a "Pentium MMX" clocked at 233MHz.
> >
> > there is no fan.  it's creepy how quiet it is.  in fact, sometimes i
> > have to look over to it just to get a mental confirmation that the damn
> > thing is on.   have to admit, i've forgotten how nice it is to not have
> > a fan on a machine.

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