To enable fan control, the module parameter fan_control=1 must be given to thinkpad-acpi.

For example, in Ubuntu 8.04 (Hardy Heron), add the following to /etc/modprobe.d/options: options thinkpad_acpi fan_control=1

Having done so, reboot and you can use the following commands to control fan speed:

# echo level 0 > /proc/acpi/ibm/fan (fan off)

# echo level 2 > /proc/acpi/ibm/fan (low speed)

# echo level 4 > /proc/acpi/ibm/fan (medium speed)

# echo level 7 > /proc/acpi/ibm/fan (maximum speed)

# echo level auto > /proc/acpi/ibm/fan (automatic - default)

# echo level disengaged > /proc/acpi/ibm/fan (disengaged)

If you receive a PERMISSION DENIED error you can use the following command syntax instead as a work-around:

# echo level 0 | sudo tee /proc/acpi/ibm/fan (fan off)

# echo level 2 | sudo tee /proc/acpi/ibm/fan (low speed)

# echo level 4 | sudo tee /proc/acpi/ibm/fan (medium speed)

# echo level 7 | sudo tee /proc/acpi/ibm/fan (maximum speed)

# echo level auto | sudo tee /proc/acpi/ibm/fan (automatic - default)

# echo level disengaged | sudo tee /proc/acpi/ibm/fan (disengaged)