Mitch Bradley wmb at laptop.org
Tue Nov 3 10:54:04 EST 2009

Emiliano Pastorino wrote:
> Mitch,
> Does q3a15 automatically throttle the processor in case of overheating?


> If so, is there a way to check if it is working? cat /proc/cpuinfo maybe?

Here is a test you can do with Open Firmware:

ok show-temperature (cr many

That command runs the CPU in full-on C0 state - no halts or other 
power-saving states - and displays the temperature.   If you have no 
heat spreader, the temperature will soon rise to 100 degrees C, and then 
the throttling will start, maintaining the temperature between 95 and 
100 degrees.  With the heat spreader, the temperature should stay much 
lower, never reaching the 100 degree throttle point.  In my current 
setup with the plastic back off, the board with the heat-spreader goes 
up to about 45 degrees.

There is a way to check the temperature under Linux.  It involves the 
"lmsensors" package, but I don't know the exact details.

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