Thinkpad Thermals

[Jesse Guardiani]

Kevin Oberman wrote:

>> From: Jesse Guardiani <jesse at wingnet.net>
>> Date: Fri, 04 Mar 2005 05:09:46 -0500
>> Sender: owner-freebsd-mobile at freebsd.org
>> 
>> Kevin Oberman wrote:
>> 
>> >> From: Jesse Guardiani <jesse at wingnet.net>
>> >> Date: Fri, 04 Mar 2005 13:01:21 -0500
>> >> Sender: owner-freebsd-mobile at freebsd.org
>> >> 
>> >> Howdy!
>> >> 
>> >> My IBM Thinkpad A30p's ATI video chip got cooked last year,
>> >> leaving me with an unreadable screen full of artifacts. I
>> >> finally bought a replacement mobo a few days ago and installed
>> >> it this evening. It's now running artifact free! Yay!
>> >> 
>> >> Anyway, I'm no longer running FreeBSD on this laptop. I'm
>> >> currently running Gentoo Linux. But it would be trivial
>> >> to switch back if needed.
>> >> 
>> >> I'm using gkrellm under linux to monitor my CPU temp, and
>> >> I'm noticing that it runs quite hot. The fan doesn't kick
>> >> in until the CPU hits 80C! That's a little too close for
>> >> comfort, IMO.
>> >> 
>> >> I think I remember seeing other posts from Thinkpad users
>> >> mentioning high temps under ACPI. Has anyone found a way
>> >> to cool these things down?
>> > 
>> > Jesse,
>> > 
>> > Is it running at or near 80C when idle, when in typical use, or when
>> > building something BIG (CPU running at >95% for minutes).
>> 
>> More or less idle. It fluctuates between 70C and 80C. Just playing an
>> MP3 I'm at 77C right now. Is this normal acceptable temp for a thinkpad?
>> Or should I be targeting the 40C range like I do with my desktop
>> machines?
>> 
> Acceptable? I suspect it is, although it seems a bit warm to me, too. My
> T30 idles at about 48C and playing MP3s pushes it up about 5 degrees, so
> your's is running a bit hotter than mine.
> 
> Laptop CPUs almost always run hotter than desktop systems. Just think
> about the fans and the big heat sink on the CPU. Your laptop has no space
> for things like that. P4s are especially bad and P4-Ms are just a bit
> better. The newer P-Ms (often call Centrino) do MUCH better, but their
> internals are very different from the P4..probably more like a
> P3. Getting heat out of a laptop is a real problem.

Sort of off topic, but interesting. I always thought the Centrino chips were
P4-Ms, but I guess not.


>> > I believe that the A30p is a P4-M CPU. It will turn itself off (hard,
>> > like a power cut-off) before the CPU dies, but that is NOT a good
>> > thing. That does not happen until the CPU reaches a frightening 135C.
>> 
>> Actually, I think mine is a P3-M at 1.2ghz. It uses PC133 SODIMMs, and
>> /proc/cpuinfo reveals this:
>> 
>> Intel(R) Pentium(R) III Mobile CPU      1200MHz
>> 
>> I think it's the A31p that uses a P4-M.
> 
> Sorry. The P3s generally run much cooler than the P4s. Is your fan
> running?

It doesn't *seem* to kick in until temp hits 80C. I don't remember seeing
anything about this in the BIOS, but I'll certainly look again. 


> It should be at those temperatures. It's under BIOS control in 
> my T30, but you would have to dump your ACPI tables to see if there is
> any fan control available.

Is there a howto for doing this? I can load FreeBSD temporarily on a spare
disk if it'll help me get to the bottom of this.


>> > If you are running 5-Stable or 6-Current you should load cpufreq and
>> > acpi_perf. These will give you a large number of CPU "frequencies"
>> > visible in dev.cpu.0 and settable in dev.cpu.0.freq. This provides
>> > fine-grained control.
>> 
>> I asked this question here mostly because I know a lot of people on this
>> list run Thinkpads, and I remember more than one complaining about
>> cooling issues.
>> 
>> Again, I no longer run FreeBSD on this laptop. I run Gentoo. Linux has
>> various different daemons capable of throttling the CPU though, and I
>> currently have an "on-battery" runlevel setup that runs the speedfreq
>> daemon with a preference for "powersave". I could install something in
>> my default "on-AC" runlevel that regulates CPU based on load even when
>> on AC...
>> 
>> But... is 80C normal under load? Running a frequency daemon won't change
>> the under-load temp unless I cap the horsepower or introduce some sort
>> of temp related frequency feedback control as you describe below.
>> 
>> Hmmm... well that's interesting: Just to test it out, I unplugged the
>> AC and ran it for a while, still playing the same MP3. It leveled out
>> at 66C in the "powersave" profile, which means that the CPU is running
>> at just 799.457mhz instead of 1199.185mhz (performance).
>> 
>> Is 66C acceptable temp for a laptop? It's definitely a better temp, but
>> It would really stink if my 1.2ghz had to be run at just 800mhz all the
>> time to avoid cooking things.
> 
> Once again, I can't define "acceptable". It is not so hot as to be
> frightening, but it does sound like it's running warmer than I would
> expect. Dust? Blocked air intake/outlet?

Absolutely not. I just replaced the motherboard myself. It took 2 hours.
I was very careful to examine the heatsink for blockage or excessive dust.
It's clean, and the fan spins freely.


> Those can real impact thermals. And, of course, fan problems can be
> a big issue. 

I'm starting to think that my fan should be running, but isn't. The
whole purpose of this post is to see if I can figure out what went wrong
last year when my GPU cooked. If the fan should be running, but isn't,
then that certainly gives me a place to start.

-- 
Jesse Guardiani, Systems Administrator
WingNET Internet Services,
P.O. Box 2605 // Cleveland, TN 37320-2605
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