[ltp] Sensors still an issue?

[Bjorn Knutsson]

On 30 May 2002 12:11, Boyan wrote:
> James,
> 
> On Thu, 30 May 2002, James Holden wrote:
> 
> > That's strange. I though the fan speed was a hardware issue. Imagine
> > your Windows OS crashes in an infinite, processor-intensive loop. The
> > software can't control the fan any more so your CPU cooks. Can't
> > imagine that's the case!
> >
> > My TP600X regulates the fan just fine and always has done.
> 
> Do you mean that the fan stops from time to time? That would be
> wonderful. Question is how to achieve this? Do you have lm_sensors
> installed and did you ever run sensors-detect? I have good control
> over the harddisk spin-down, but not on the fan.

lm-sensors has nothing to do with this, it will as far as I know only
tell you the temperature, not actually do anything about it. I ran
lm-sensors once on my machine. Next time I rebooted, it had turned
into an expensive doorstop. Now, my excuse was ignorance, only several
months later did the lm-sensors alert surface, and I realized that
yes, I had ran lm-sensors the last time the machine ran before it
refused to boot again. It didn't seem to work anyway, so I had erased
it by the time I rebooted.

Anyway, my old 600X would run the fan for a while, and then stop. If
you haven't enabled APM, this could be the reason - with APM, you make
calls to the APM BIOS when you're idle that allows the processor to
run cooler.

My newer T23 works exactly the same - the fan will run for a while,
and then stop, unless I'm doing something CPU intensive. The thing
that bug me with the T23 is that the harddisk is under the "hand
rest"-part of the laptop, and it gets pretty warm. The 600X was always
nice and cool.

> > It may be worth playing with the options in tpctl.
> 
> Do you know of some options that give control over the fan. Well, I
> tweaked different CPU options but to no avail. It seems the tpctl
> cannot change the speed on the fly on my machine. If it is booted high
> it stays high.

As far as I know, no. There is nothing you can do to directly control
the fan, and I doubt you'd want to. It's running for a reason - to
keep your CPU from going up in smoke. (Did you see the video of a
heat-sink free Athlon from Tom's hardware? Burn, baby, burn!)

Now, I do remember something about a BIOS problem involving the fan,
so unless your BIOS is updated, you could try that, but the fact that
it's behaving correctly under Windows seems to suggest to me that you
want to check a) That you're using a kernel with proper APM-support
compiled in and enabled and b) That you're not running something
that's gobbling CPU in the background.

But do not try to stop the fan, and do not run lm-sensors. Both are
very likely to land you with an expensive paper weight.

/Björn

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