CPU Overheating?

[Roland Smith]

On Mon, Mar 31, 2014 at 12:11:43AM +0000, Walter Hurry wrote:
> I have a bog-standard Acer laptop with FreeBSD 9.2 (amd64).
> 
> CPU is  AMD Athlon(tm) 64 X2 Dual-Core Processor TK-42 (1596.09-MHz K8-class CPU) per dmsg.
> 
> >From time to time, it shuts off without warning, as if the power cable has been pulled out. Nothing in any of the logs, and when I power up again it starts normally after replaying the journal.
> 
> The shut-off is invariably when it is doing a compile of a big port. I therefore suspect that the CPU is overheating and that the BIOS is causing the shutdown.
> 
> To investigate the problem, I have done a 'kldload coretemp' and am periodically running:
>  'sysctl hw.acpi.thermal.tz0.temperature'. So far (only 6 runs) this is reporting temperatures between 76C and 84C.
> 
> Question 1: Is this the canonical way to monitor CPU temperature?

It's OK. If you want to see all sysctls that are relevant, try:

    sysctl -a | grep temperature

> Question 2: Is this too hot?

It is quite hot for a system that is idling. I get around 48-50 °C on an Intel core 2.

Check that the CPU fan is running and that the fan and heat-sink are clean.
Dust blocking airflow through the heat-sink killed the GPU in my laptop last year. :-(

> Question 3: I plan to load the module in /boot/loader.conf and set up a cron job to run every minute and log the result to a file. Is this sensible, or overkill?

You can also use programs like conky to show the temperature on your desktop
(if you're running X11).

Roland
-- 
R.F.Smith                                   http://rsmith.home.xs4all.nl/
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