Ubuntu 10.04风扇声音太大

我的台式机(3.20GHz Pentium Dual CPU E5800,4G RAM,独立显卡,双硬盘，一个装了Ubuntu 10.04，一个装了WIN7)在Ubuntu 10.04下风扇声音很大，但是在WIN7下风扇声音很小，于是上网搜索了一下，说pwmconfig可以解决这个问题，于是就用它设置了一下(装lm_sensors之类的，具体请自行google)，但是还是没变化，有点郁闷，仔细阅读了pwmconfig的说明，觉得可能是/etc/fancontrol中的MINSTART和MINSTOP设置的有问题，于是就改了改，现在的fancontrol配置如下(最关键是最后三行):

$ cat /etc/fancontrol
# Configuration file generated by pwmconfig, changes will be lost
INTERVAL=10
DEVPATH=hwmon2=devices/platform/it87.2576
DEVNAME=hwmon2=it8720
FCTEMPS= hwmon2/device/pwm1=hwmon2/device/temp1_input
FCFANS= hwmon2/device/pwm1=hwmon2/device/fan1_input
MINTEMP= hwmon2/device/pwm1=20
MAXTEMP= hwmon2/device/pwm1=60
MINSTART= hwmon2/device/pwm1=50
MINSTOP= hwmon2/device/pwm1=0
MAXPWM= hwmon2/device/pwm1=120

重启机器，好了，风扇比在WIN7下还安静，再查看一下风扇状态:
$ sensors
coretemp-isa-0000
Adapter: ISA adapter
Core 0: +35.0°C (high = +76.0°C, crit = +100.0°C)

coretemp-isa-0001
Adapter: ISA adapter
Core 1: +27.0°C (high = +76.0°C, crit = +100.0°C)

it8720-isa-0a10
Adapter: ISA adapter
in0: +1.09 V (min = +0.00 V, max = +4.08 V)
in1: +2.99 V (min = +0.00 V, max = +4.08 V)
in2: +1.52 V (min = +0.00 V, max = +4.08 V)
in3: +2.98 V (min = +0.00 V, max = +4.08 V)
in4: +3.02 V (min = +0.00 V, max = +4.08 V)
in5: +1.14 V (min = +0.00 V, max = +4.08 V)
in6: +3.41 V (min = +0.00 V, max = +4.08 V)
in7: +2.98 V (min = +0.00 V, max = +4.08 V)
Vbat: +3.15 V
fan1: 983 RPM (min = 0 RPM)
fan2: 0 RPM (min = 0 RPM)
fan3: 0 RPM (min = 0 RPM)
temp1: +33.0°C (low = -1.0°C, high = +127.0°C) sensor = thermal diode
temp2: +29.0°C (low = -1.0°C, high = +127.0°C) sensor = thermistor
temp3: +24.0°C (low = -1.0°C, high = +127.0°C) sensor = thermal diode
cpu0_vid: +0.000 V

风扇保持在900-1000 RPM，夜深人静的情况下也非常安静，不错，不错。至今还没发现机器有异常(CPU温度过高之类的)

P.S.我的机器环境如下:
$ uname -r
2.6.32-28-generic-pae