aaron c beals

so the other day i mentioned that i was working on fixing the fan noise in my Thinkpad laptop. originally, i investigated some stand-alone software (tpfancontrol) for fan control, but i was really looking for something to hook into Notebook Hardware Control (NHC), so i could manage all operational aspects of my laptop from one console. in fact, NHC claimed to cover fan control (or at least monitoring), but I couldn’t find that information anywhere in the NHC interface. turns out that i just needed to go to the “Settings” tab and click “Show all NHC options and settings”… voila! tabs galore, including the “ACPI” tab i needed for fan monitoring and control.

the next step was to find the ACPI control scripts for my T42 Thinkpad — or else write my own from scratch. luckily, i found the scripts required thanks to Aaron Tiensivu’s blog. just download this zip and follow the instructions in the readme file.

the default mode for the script is to turn on ACPI control through NHC, so that the fan is tied to the CPU and HDD temperatures (which makes sense, right?) — and the default temperature settings seem conservative. i have been monitoring the CPU temp closely to make sure everything is working as promised, and so far i haven’t been frying eggs on the keyboard.

the only odd thing is that NHC cycles through the fan speeds on startup and when you come back from sleep mode, so if you’re not prepared for that, it’s a little strange. the fan will rev up to top speed and then drop back to zero, which as far as i can tell is used to check that all the speed levels are valid.

in the end, the whole ACPI-script process took me about 3 minutes, and now my laptop’s fan is working normally and sanely.