siraseです。

Ubuntu環境でCPUファンの制御をする方法を調べて挑戦していますが
うまくいかず困っていますので、お知恵をお貸し下さいませ。

$ sudo apt-get install lm-sensors fancontrol

でファンの制御に必要なパッケージをインストールし、

$ sudo sensors-detect

で、ハードウェアの検出を行い、it87というモジュールで制御できそうな事が分かりました。
sensors-detectの最後の質問に「yes」と答えると、自動的に /etc/modules に下記が追記されました。

# Generated by sensors-detect on Fri Jun 28 10:34:41 2013
# Chip drivers
it87

その後

$ sudo modprobe -v it87

をすると、正常にit87モジュールをロードできました。

$ lsmod | grep -i it87
it87                   28873  0 
hwmon_vid              12687  1 it87

で確認できます。

この状態で、

$ sudo pwmconfig

を実行すると、何やら色々質問されます。

$ sudo pwmconfig
# pwmconfig revision 5857 (2010-08-22)
This program will search your sensors for pulse width modulation (pwm)
controls, and test each one to see if it controls a fan on
your motherboard. Note that many motherboards do not have pwm
circuitry installed, even if your sensor chip supports pwm.

We will attempt to briefly stop each fan using the pwm controls.
The program will attempt to restore each fan to full speed
after testing. However, it is ** very important ** that you
physically verify that the fans have been to full speed
after the program has completed.

Found the following devices:
   hwmon0 is acpitz
   hwmon1/device is it8718

Found the following PWM controls:
   hwmon1/device/pwm1
   hwmon1/device/pwm2
   hwmon1/device/pwm3

Giving the fans some time to reach full speed...
Found the following fan sensors:
   hwmon1/device/fan1_input     current speed: 20 RPM
   hwmon1/device/fan2_input     current speed: 0 ... skipping!
   hwmon1/device/fan3_input     current speed: 0 ... skipping!

Warning!!! This program will stop your fans, one at a time,
for approximately 5 seconds each!!!
This may cause your processor temperature to rise!!!
If you do not want to do this hit control-C now!!!
Hit return to continue:

Testing pwm control hwmon1/device/pwm1 ...
  hwmon1/device/fan1_input ... speed was 20 now 0
    It appears that fan hwmon1/device/fan1_input
    is controlled by pwm hwmon1/device/pwm1
    Fan hwmon1/device/fan1_input has not returned to speed, please investigate!

Testing pwm control hwmon1/device/pwm2 ...
  hwmon1/device/fan1_input ... speed was 20 now 0
    It appears that fan hwmon1/device/fan1_input
    is controlled by pwm hwmon1/device/pwm2
Would you like to generate a detailed correlation (y)?
    PWM 255 FAN 10
    PWM 240 FAN 10
    PWM 225 FAN 10
    PWM 210 FAN 10
    PWM 195 FAN 10
    PWM 180 FAN -1
    Fan Stopped at PWM = 180


Testing pwm control hwmon1/device/pwm3 ...
  hwmon1/device/fan1_input ... speed was 20 now 709
    no correlation

No correlations were detected.
There is either no fan connected to the output of hwmon1/device/pwm3,
or the connected fan has no rpm-signal connected to one of
the tested fan sensors. (Note: not all motherboards have
the pwm outputs connected to the fan connectors,
check out the hardware database on http://www.almico.com/forumindex.php)

Did you see/hear a fan stopping during the above test (n)? y

Testing is complete.
Please verify that all fans have returned to their normal speed.

The fancontrol script can automatically respond to temperature changes
of your system by changing fanspeeds.
Do you want to set up its configuration file now (y)?
What should be the path to your fancontrol config file (/etc/fancontrol)?

Select fan output to configure, or other action:
1) hwmon1/device/pwm3  4) Change INTERVAL     7) Show configuration
2) hwmon1/device/pwm2  5) Just quit
3) hwmon1/device/pwm1  6) Save and quit
select (1-n): 3

Devices:
hwmon0 is acpitz
hwmon1/device is it8718

Current temperature readings are as follows:
hwmon0/temp1_input    40
hwmon1/device/temp1_input    25
hwmon1/device/temp2_input    -128
hwmon1/device/temp3_input    26

Select a temperature sensor as source for hwmon1/device/pwm1:
1) hwmon0/temp1_input
2) hwmon1/device/temp1_input
3) hwmon1/device/temp2_input
4) hwmon1/device/temp3_input
5) None (Do not affect this PWM output)
select (1-n): 1

Enter the low temperature (degree C)
below which the fan should spin at minimum speed (20):

Enter the high temperature (degree C)
over which the fan should spin at maximum speed (60):
/usr/sbin/pwmconfig: 926 行: [: -eq: 単項演算子が予期されます
/usr/sbin/pwmconfig: 952 行: [: -eq: 単項演算子が予期されます

Enter the PWM value (0-255) to use when the temperature
is over the high temperature limit (255):


Select fan output to configure, or other action:
1) hwmon1/device/pwm3  4) Change INTERVAL     7) Show configuration
2) hwmon1/device/pwm2  5) Just quit
3) hwmon1/device/pwm1  6) Save and quit
select (1-n): 7

Common Settings:
INTERVAL=10

Settings of hwmon1/device/pwm3:
  Depends on
  Controls
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

Settings of hwmon1/device/pwm2:
  Depends on
  Controls
  MINTEMP=
  MAXTEMP=
  MINSTART=
  MINSTOP=

Settings of hwmon1/device/pwm1:
  Depends on hwmon0/temp1_input
  Controls
  MINTEMP=20
  MAXTEMP=60
  MINSTART=150
  MINSTOP=0


Select fan output to configure, or other action:
1) hwmon1/device/pwm3  4) Change INTERVAL     7) Show configuration
2) hwmon1/device/pwm2  5) Just quit
3) hwmon1/device/pwm1  6) Save and quit
select (1-n): 6

Saving configuration to /etc/fancontrol...
Configuration saved

そして、最終的に出来上がった設定ファイルが
/etc/fancontrol

# Configuration file generated by pwmconfig, changes will be lost
INTERVAL=10
DEVPATH=hwmon0= hwmon1=devices/platform/it87.2576
DEVNAME=hwmon0=acpitz hwmon1=it8718
FCTEMPS=hwmon1/device/pwm1=hwmon0/temp1_input
FCFANS= hwmon1/device/pwm1=
MINTEMP=hwmon1/device/pwm1=20
MAXTEMP=hwmon1/device/pwm1=60
MINSTART=hwmon1/device/pwm1=150
MINSTOP=hwmon1/device/pwm1=0

のようになっています。
しかし全くファンの音は静かにならず常にフルスピード状態で動いている様に思います。
ファンの音がうるさいです。

どうすれば静音化出来るのでしょうか？よく分からず困っています。

どうぞご教示の程よろしくお願い致します。