Re: Thermal problems with newer kernels

From: Robert Hancock
Date: Wed Jan 28 2009 - 19:44:58 EST


Andrew Watts wrote:
Dear Kernel Gurus:

Below is a problem that I am unable to explain along with relevant(?) info. Please let me know if I should provide additional debugging information. Thanks in advance for your assistance!

-Andy

[1] Problem: HP Pavilion zv5000 laptop idle temp is 17 degrees higher when running most recent kernels (57C versus 40C).

[2] Brief Description

Newer kernels (noticed starting with 2.6.27.3 but could have started anytime past 2.6.26.7) result in a much higher idle CPU temp. Physical temperature reading of exhaust from primary cooling fan and the regular triggering of secondary cooling fan confirms this (it is not a readout scaling issue). The kernels and temps below:

2.6.26.7 Idle temp 40C
2.6.27.3 Idle temp 57C
2.6.28 Idle temp 57C

The only third party kernel module installed that is not part of the official kernel source is: madwifi-ng. However, the problem occurs even when this module is not loaded.

The .config file used for the newer kernels was imported from the working 2.6.26.7 .config file.

CPU frequency scaling not working perhaps? What's your dmesg output from bootup look like? Is the acpi-cpufreq driver being loaded?
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