I have been looking into some thermal shutdown issues with our board, and discovered that LinuxBIOS is not enabling the P4's ability to throttle back when the internal sensors indicate that the processor is getting too hot.
According to the System Programming Guide, Vol. 3 of the IA-32 Intel Architecture Software Developer's Manual (p. 13-24):
"BIOS is required to enable only one automatic thermal monitoring modes (sic). Operating systems and applications must not disable the operation of these mechanisms."
Has this been considered for LB? I didn't see any discussions in the mailing list archives.
It would be relatively easy to implement support for "TM1" thermal control, since that's just setting a MSR bit if the proper CPUID flag is set. "TM2" control would be a little more complicated, since there is the added ability to control the operating frequency and voltage when the processor trips into thermal management mode.
Steve www.digidescorp.com