Howto: Reduce fan noise level on the eee pc 900 / 1000 / 1000H : Part II
This article is a continuation of a previous post on how to contol the fan on the eee pc. I have updated the fan control code to version 2 which uses a slightly more advanced mathematical function (a sigmoid function) when calculating the best fan speed for a given temperature.
Installation instructions
The first thing you need to do is to install Adams custom kernel for the eeepc. He has a nice guide on how to do that here. To automate the fan adjustment, I have written a small script (with the name eeefan) which can be seen below. You may copy-paste it, or download it here. I suggest that you put it in you ~/bin/ folder. Once you have done this, add the following line to the file /etc/crontab:
*/1 * * * * root sh /home/username/bin/eeefan2
Remember to replace username by your real user name. Also, add the line
asus_eee
to the file /etc/modules. Now, the fan speed will be automatically adjusted every 10 seconds.
eeefan Code:
# !/bin/sh
# K.H. Jensen 2008 // www.hartvig.de
# Released under the GPL
# eeefan version 2 - eee pc fan control utility
temperature_reading=/proc/eee/temperature
fan_control=/proc/eee/fan_speed
fan_manual_switch=/proc/eee/fan_manual
# Set critical temperature
TEMP_CRITICAL=57
# Set critical temperature interval size. See figure for details
TEMP_INTERVAL_SIZE=5
# Maximum fan speed
FAN_SPEED_MAX=55
eeefanupdate() {
# Get temperature reading
TEMP=$(cat $temperature_reading)
# Calculate optimum fan speed
X=$(echo "$FAN_SPEED_MAX*1/(1+e(-($TEMP-$TEMP_CRITICAL)/$TEMP_INTERVAL_SIZE))" | bc -q -l)
# Workaround to convert it to nearest integer
FAN_SPEED=$(echo "scale=0; $X/1.0" | bc -q -l)
# Set fan speed
echo $FAN_SPEED > $fan_control
}
# cron jobs can only be executed once every minute,
# so we have to use the sleep command
# Turn on manual fan control
echo 1 > $fan_manual_switch
# Run eeefanu, then wait 10 seconds.
eeefanupdate
sleep 10
eeefanupdate
sleep 10
eeefanupdate
sleep 10
eeefanupdate
sleep 10
eeefanupdate
That’s great work – I love the way you parse advanced math into bc
Thanks,
Just when i was getting tired of the hum in my 901, i came across this page. At least in first try, it is working like charm.
Now all that is needed is someone porting asus under and overclocking features in ubuntu. I would like to see my eee run in less than 800MHz in standard desktop use. What i found was that it is done in xandros and xp versions by adjusting bus speeds from 100 to standard 133 to overclock mode 150MHz.
Now ubuntu is only adjusting multiplier to clock cpu from 800 to 1600MHz.
With the mod it would be able to adjust from 600 to 1800MHz like in original distros. So more power when its needed and less heat when running powersave mode.
Thank you for the script. I’ve modified it so you can start it up from rc.local. Have fun!
#!/bin/bash
# based on eeefan2 by K.H. Jensen 2008 // http://www.hartvig.de
# Released under the GPL
# modified to run from rc.local
#redirect all output to /dev/null
exec &> /dev/null
temperature_reading=/proc/eee/temperature
fan_control=/proc/eee/fan_speed
fan_manual_switch=/proc/eee/fan_manual
# Set critical temperature
TEMP_CRITICAL=55
# Set critical temperature interval size. See figure for details
TEMP_INTERVAL_SIZE=5
# Maximum fan speed
FAN_SPEED_MAX=55
# Fill array fan_speed[Temperature]
for ((TEMP=0; TEMP $fan_control
}
# Turn on manual fan control
echo 1 > $fan_manual_switch
# while manual fan control is active, control the fan, otherwise quit
while [ $(cat $fan_manual_switch) -eq 1 ]; do
eeefanupdate
sleep 10
done
Hey. Cool Hack. But isn’t working correct:
fan speed rises bud does not fall depending the cpu_temp.Means after cooling a while temp. decreases but fan speed stays the same (high) level..
What’s the measure for that?
@ Johannes: Nice hack. Maybe i will write something about using rc.local at some point
@ Me(?): This is probably because you need to restart cron?
/etc/init.d/cron restart
Otherwise, try lowering TEMP_CRITICAL
Perfect! Thx a lot. Restarting cron was the right thing to do.
It worked, thanks alot =)
Thank you, thank you! That noise was making me regret the purchase of this computer. Your script works like a charm!
That sounds nice! Does it work with the eee 1008 HA?
I believe, that it will also work with the eee 1008 HA.
Hi I have a eee900 ubuntu 8.10 I am new with Ubuntu but I think I have performed correctly the procedure but it seems nothing change…the fan is still noisy and even more strange does not seem to stop even if I put the laptop for half an hour in the balcony with cold outside temperature. It’s very annoying. Thank for any advice.
Mirco, have you installed Adams custom kernel? If not, get it here.
Second thing you could try is to to restart cron. Execute (as root):
/etc/init.d/cron restart
I think, I have solved the problem. It did not work because eeefan2 was in a different path than indicated below
*/1 * * * * root sh /home/username/bin/eeefan2
mine was
*/1 * * * * root sh /file system/bin/eeefan2
I tried and it seems working properly.
Hope it can be useful for other beginners who like me simply copy and paste.
Thanks for your very effective solution. I was about to sell the laptop.
Only one question…..does this solution collapse with “eee control”? I had to remove it, because it did not work anymore after having made you suggested changes.
Thanks
Thanks so much. It works great. I’ve been looking for something like this for a very long time.
Hmm it looks like your website ate my first comment (it was extremely long) so I guess I’ll just sum it up what I wrote and say, I’m thoroughly enjoying your blog. I too am an aspiring blog writer but I’m still new to everything. Do you have any tips for inexperienced blog writers? I’d genuinely appreciate it.