How to check fan speed?

[Aleksandar Milivojevic]

Quoting "Poluri, Ramachandra Rao" <rp230050 at ncr.com>:

> Please help how to find out the fan speed on my Linux machine & how to
> change the settings related to it..

Install lm_sensors package (if you don't have it already).  As root,  
run sensors-detect.  It will attempt to detect what sensor chips you  
have on the motherboard.  Not all chips are supported, and support  
varies by the version of lm_sensors (you'll probably have more luck  
with newer motherboards under Fedora Core, than in Enterprise Linux).

At the end, the "sensors-detect" will instruct you to edit some files.  
  You can skip that.  The sensors-detect will update everything  
needed, and there's lm_sensors service (in /etc/init.d) that does boot  
time initialization.

Once everything is setup, you can use "sensors" command (either as  
root or normal user) to read out information about fans, temperatures  
and voltages.  You can set alarm levels in /etc/sensors.conf (under  
your chipset's section), however every time you change it you'll have  
to run "sensors -s" as root for new settings to take effect.  Usually  
you'll need to tweak alarm levels, esp. if you have variable speed fans.

Hope this helps.