root@boreale:~# cat /proc/acpi/ibm/fan 
status:		enabled
speed:		3322
level:		disengaged
commands:	level <level> (<level> is 0-7, auto, disengaged, full-speed)
commands:	enable, disable
commands:	watchdog <timeout> (<timeout> is 0 (off), 1-120 (seconds))

# ... wait a minute or so ...

root@boreale:~# cat /proc/acpi/ibm/fan 
status:		enabled
speed:		5026
level:		disengaged
commands:	level <level> (<level> is 0-7, auto, disengaged, full-speed)
commands:	enable, disable
commands:	watchdog <timeout> (<timeout> is 0 (off), 1-120 (seconds))