How To Find Out Fan Speed Via Software

[Robin Laing]

John Summerfield wrote:
> Robert L Cochran wrote:
>> Is there a way to find out the cpu fan speed through software -- a 
>> shell script or other utility maybe? I'd like some way to monitor cpu 
>> fan speed and get a notification if the fan quits unexpectedly.
> 
> You need lm-sensors
> 
> 
> run sensors-detect as root, agree with everything. Then,
> [root at mail httpd]# LANG=C sensors
> eeprom-i2c-0-51
> Adapter: SMBus I801 adapter at e000
> Memory type:            DDR SDRAM DIMM
> Memory size (MB):       256
> 
> eeprom-i2c-0-50
> Adapter: SMBus I801 adapter at e000
> Memory type:            DDR SDRAM DIMM
> Memory size (MB):       256
> 
> adm1025-i2c-0-2d
> Adapter: SMBus I801 adapter at e000
> +2.5V:     +1.48 V  (min =  +0.00 V, max =  +3.32 V)
> VCore:     +1.48 V  (min =  +0.00 V, max =  +2.99 V)
> +3.3V:     +3.30 V  (min =  +0.00 V, max =  +4.38 V)
> +5V:       +5.08 V  (min =  +0.00 V, max =  +6.64 V)
> +12V:      +0.00 V  (min =  +0.00 V, max = +15.94 V)   ALARM
> VCC:       +3.27 V  (min =  +0.00 V, max =  +4.38 V)
> CPU Temp:  +38.0 C  (low  =    +0 C, high =  +127 C)
> M/B Temp:  +34.0 C  (low  =    +0 C, high =  +127 C)
> 
> [root at mail httpd]#
> 
> I have seen fan speed mentioned.
> 

Word of warning.

What I did find out about sensors is the accuracy of the voltages can be 
wrong.  Take note that this could give a false sense of security.  I had 
a PSU failing but sensors didn't read the voltage correctly.  I lost a 
DVD burner and almost lost a hard drive due to this.  You can play with 
the settings and calibrate the settings.

I confirmed my settings with a good digital volt meter.

I was reminded of this when I saw the ALARM in the above link.
-- 
Robin Laing