Different Fan Behaviour on ThinkPad X61 than X31

Since I got my new Lenovo ThinkPad X61, I have discovered that the CPU fan is behaving rather differently than the one I have in my IBM ThinkPad X31. That is the fan makes a lot more noise when idle on the X61.

For the record. I’m running Ubunty Hardy (8.04) on the X61 and Ubuntu Gutsy (7.04) on the X31. Both 32-bit systems.

The first thing I did was checking Launchpad.net for any known bugs. I found bug 224876 to be promising, it’s titled “Hardy does not control the CPU fan properly.”
After reading this thread I ran the tests described myself, which gave these results.

Machine temperature and fan speed when idle (X61):

$ cat /proc/acpi/thermal_zone/THM0/temperature
temperature: 41 C
$ cat /proc/acpi/thermal_zone/THM1/temperature
temperature: 42 C
$ cat /proc/acpi/ibm/fan
status: enabled
speed: 3207
level: auto

After 5 minutes of “yes | sha512sum” (X61):

$ cat /proc/acpi/thermal_zone/THM0/temperature
temperature: 76 C
$ cat /proc/acpi/thermal_zone/THM1/temperature
temperature: 78 C
$ cat /proc/acpi/ibm/fan
status: enabled
speed: 3242
level: auto

As you can see there is as good as no change in the fan speed.
However; doing the same check on my older, one core, IBM ThinkPad X31.
I get this results:

Machine temperature and fan speed when idle (X31):


$ cat /proc/acpi/thermal_zone/THM0/temperature
temperature: 44 C
$ cat /proc/acpi/ibm/fan
status: enabled
speed: 0
level: auto

Actually, the fan doesn’t start until the temperature reach 68 degrees Celsius. Then it will speeds up to around ~3500 rpm, thus keeping the processor at around 70 degrees Celsius during “yes | sha512sum”.

My question is: Why does the fan constantly run on the X61? Is it really necessary to keep the processor cool? I must say I prefer the silence of the X31 when I’m just browsing the web.

Karl Trygve has suggested that this is a result of a new design team and BIOS which is more restrictive than the one found on the X31.

5 thoughts on “Different Fan Behaviour on ThinkPad X61 than X31

  1. I have X61t and the fan noise is killing me. I have a hp Laptop with the similar processor and the fan barely makes any noise!

  2. You need a ‘fan control’ program. There are two or three candidates out there that I know of.
    In order of how useful they look:

    One is ‘tpfancontrol’, just put it into google. This was written for T40 series, however I have tried it on my X61 very quickly, and it *seems* to work. (two disclaimers here, I have only tried it very briefly so far with all looking good, and dont blame me if you use it and you melt your CPU!)
    The other is ‘notebook hardware control’, which has some scripts for older thinkpads on there. However, this program doesn’t seem 100pc compatible with the thinkpad x61 a) I couldnt modify the ACPI scripts to recognize my X61 although it did recognize my X32, b) I was having trouble with its hard-drive control systems.

    There is also ‘speedfan’, I don’t know much about this.
    Same disclaimers apply to these two latter programs.

    Good luck.

  3. use the tffancontrol and put it in smart mode 2. Remove the acceleration in properties/troubleshooting. In the manage system, disable the finger scanner, lan, wifi and modem. Use a usb wifi instead. My temperature around 47 to 55. When the temp reaches 60, the fan will spin fast then afterwards return to normal.

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