Motherboard temperatures

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One of the important things when you plan on overclocking a system is to have an eye on the system temperature. Some systems are providing all data you need through ACPI and it is shown in the /proc/acpi/thermal_zone/ folder.

However my /proc/acpi/thermal_zone/ folder is empty. I thought that this was because a bad ACPI implementation. You know, the BIOS contains a description of the capabilities of the hardware that is handed over to ACPI and it is called dsdt. Sometimes this file is broken and it contains errors but because they only test it against some version of Windows some errors are not fixed.

You can extract your system's dsdt and fix it yourself. Linux boot process can either use the dsdt provided by BIOS or it can use a fixed copy you create on initrd. To do the latter, you need a patched kernel. The kernel that ships Ubuntu's Dapper Drake is already patched to support this feature, so you can store your patched dsdt to /etc/mkinitramfs/ and name it exactly as DSDT.aml and do a sudo dpkg-reconfigure linux-image-`your-current-version` and that's all.

However, my dsdt file did not contain errors but warnings I could not fix. And although time consuming the task did not cure my problem of not having access to the temperature measurements of my motherboard (Asrock775Twins-HDTV R2.0). I hope the new BIOS version, when available, will fix the situation, but for the moment ACPI is not the way to get the temperature with this motherboard.

So what I did was to look back for non-ACPI ways of getting the temperature information. And I have found this tutorial that worked for me.

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