CPU Overheating?

[Walter Hurry]

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?
Question 2: Is this too hot?
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?

Thanks.