FreeBSD shutting down due to overheat on Lenovo T61

During long software compilations, FreeBSD was shutting down my laptop due to very high temperature.
After some research, I manage to have a stable system and build big ports without problems:

-First and foremost, re-apply thermal paste on your processor and GPU chip.

-Make sure your heat sink and fan are clean.

-Configure the system to load the ACPI module during boot time, loader.conf must have:

acpi_ibm_load="YES"
coretemp_load="YES"

coretemp will help you get additional temperature-related details.

You can monitor the temperature via sysctl, example:

# sysctl -a | grep temperature

-Adjust the ACPI module parameters. In my case, the following values helped to get a good temperature/performance balance:

# grep acpi /etc/sysctl.conf
hw.acpi.thermal.user_override=1
hw.acpi.thermal.polling_rate=2
hw.acpi.thermal.tz1._PSV=85.0C

Further details about them at acpi_ibm man page.