Preventing Shutdown Due to Overheating

[chetreb]

I want to study the behaviour of a Pentium 4 processor (with Ubuntu 8.04)
at high temperatures (around 80deg C).
However I cannot get to that temperature because the system shuts down at 60degs.
Is there a way to disable the shut down, or change the temperature at which the
system will shut down.

I have already looked in the BIOS, and found no way to do this.

[Patrick_F_Intel1]

Hello Chetreb,
The thermal shutdown is designed to avoid heat damage tothe processor.
Even if there was a way to raise the shutdown temperature, I doubt Intel would publish this info since malicious virus writers could use it to damage cpus.
I'll check what the Intel official policy is but don't hold your breath on this one.
Pat

[chetreb]

Thanks for the reply Pat

I would like to know who commands the shutdown; the operating system or the processor itself.
How does the shutdown on overheating work ?
Is there an interrupt which gets triggered on high temperature or a signal which directly resets the processor.

Chetreb

[Patrick_F_Intel1]

Please read (from http://www.intel.com/products/processor/manuals/) "Intel 64 and IA-32 Architectures Software Developer's Manual Combined Volumes 3A and 3B: System Programming Guide, Parts 1 and 2", Chapter 14, especially section 14.5.
The catastrophic shutdown mechanism due to high temperatures is not visibleto software.

[Darrell_B_]

I have an E210882 board that shuts down before I can access the bios fan on processor blowing 90mph.

[Patrick_F_Intel1]

Please provide more detail so we can decide if this is the appropriate forum for this type of question.

[SergeyKostrov]

>>...The catastrophic shutdown mechanism due to high temperatures is not visibleto software... What about Operating System? At least it should be able to close everything ( open files, etc ) properly before the Power is turned off.

[Patrick_F_Intel1]

Hello Sergey,

By the nature of 'catastrophic shutdown', I'm guessing that the choice is: 1) give the OS time to do an orderly shutdown or 2) fry the chip.

The OS gets info before the catastrophic level so that the OS can try to cool down the chip (such as by throttling the frequency).

Here is a termperature FAQ http://www.intel.com/support/processors/sb/CS-033342.htm

For each processor there is a "Thermal and Mechanical Design Guide" guide like http://www.intel.com/content/dam/www/public/us/en/documents/design-guides/3rd-gen-core-lga1155-socket-guide.pdf which goes into some detail about all the thermal safeguard layers present in the chip.

Pat

[Patrick_F_Intel1]

Hello Sergey,

By the nature of 'catastrophic shutdown', I'm guessing that the choice is: 1) give the OS time to do an orderly shutdown or 2) fry the chip.

The OS gets info before the catastrophic level so that the OS can try to cool down the chip (such as by throttling the frequency).

Here is a termperature FAQ http://www.intel.com/support/processors/sb/CS-033342.htm

For each processor there is a "Thermal and Mechanical Design Guide" guide like http://www.intel.com/content/dam/www/public/us/en/documents/design-guides/3rd-gen-core-lga1155-socket-guide.pdf which goes into some detail about all the thermal safeguard layers present in the chip.

Pat

[Bernard]

Pat can hardware overheat protection override the software(OS or acpi bios) in case of handling catastrophic shutdown? I mean what can happen when for example OS code which is trying to lower cpu frequency crashes or is unresponsive.