[CentOS] Fan speed control on Supermicro X8DAL board with CentOS

Sun Feb 6 17:48:59 UTC 2011
Ned Slider <ned at unixmail.co.uk>

On 06/02/11 17:15, Chuck Munro wrote:
> On Sun, 06 Feb 2011 12:09:12 +0000  Ned Slider wrote:
>> On 06/02/11 07:00, Chuck Munro wrote:
>>>> Hello folks,
>>>> I'm having a difficult time trying to figure out why the CPU cooling
>>>> fans run at full speed on my Supermicro X8DAL-3 motherboard.  There
>>>> doesn't seem to be any variable speed (the fans are PWM compatible) ...
>>>> they either idle at almost nothing, or suddenly burst into a
>>>> high-pitched scream that gets my ears bleeding after a few seconds.
>>>> Once they jump to warp-10, they remain there.
>>>> The "Super-I/O" chip on this board is a Winbond W83627DHG which does the
>>>> temperature and voltage monitoring.
>>>> Is anyone aware of which driver or kernel module I need for that chip in
>>>> order to get control of the fans?  The Supermicro web site and the
>>>> board's manual aren't any help.  Fresh installs of CentOS-5.5 and RHEL-6
>>>> don't exert any control by default.  Installing the lm_sensors package
>>>> and probing with the 'sensors' command didn't help either.
>>>> Slowly going deaf .......
>>>> Chuck
>> Hi Chuck,
>> The correct kernel module for your chipset is w83627ehf.ko. I'm not sure
>> the driver actually controls fan speed, I thought it was more for
>> monitoring (fan speeds, temps, voltages) but I could be wrong. My
>> current system (not a Supermicro) controls variable fan speed from
>> options within the BIOS. I can enable/disable fan speed control and
>> select either voltage or PWM based control.
>> The stock w83627ehf driver in RHEL5.5 is oldish (they were updated in
>> 5.5 I think but are still over a year old now). ELRepo.org have an
>> updated driver available (kmod-w83627ehf) based on a backport from
>> kernel-2.6.34. I've just checked upstream and a few more patches have
>> been committed since kernel-2.6.34 and the current kernel-2.6.37 so I'll
>> look at updating the elrepo driver with those latest patches.
>> Hope that helps.
> Thanks Ned!  I did go through the board's BIOS menus several times and
> could find only one fan control option, which ranges from always-fast
> for maximum performance to almost-silent for workstation use.  No matter
> what the setting, the fans may start out slow but eventually jump to
> high speed.  Updating the BIOS to the latest version made no difference.
>    I also noticed that at all times the BIOS reports the CPU temperatures
> as "Low" no matter what the fan speed.  The coolers are always cold to
> the touch.
> I sure hope I don't have a defective board ... it's a royal pain to have
> to remove one from a large server.  I booted Ubuntu but the live-CD
> version doesn't have a working 'fancontrol' utility.  I'd be tempted to
> install Ubuntu Server but I much prefer staying with CentOS and KVM to
> match all of the guest virtual machines it'll be running.
> Time to go through the mobo manual with a fine-tooth comb.  :-)
> Chuck

You're welcome Chuck.

Your question prompted me to update the elrepo kmod-w83627ehf driver 
package to the latest upstream source (kernel-2.6.37):


By all means give that package a try, but I'm not convinced it will 
address your problem in this case. Either way, it should be relatively 
quick and painless to test - updated packages should be available shortly.

Maybe someone with more experience of this particular Supermicro M/B 
will pop up on the list :-)