Review your favorite Linux distribution.
Go Back > Forums > Linux Forums > Linux - Distributions > Fedora
User Name
Fedora This forum is for the discussion of the Fedora Project.


  Search this Thread
Old 05-03-2005, 12:23 AM   #1
Registered: Jul 2003
Distribution: Fedora Core 2, RH 9
Posts: 33

Rep: Reputation: 15
cpuspeed scaling wrong when booting from battery in FC2

I have an Inspiron 8600 with Pentium M 2Ghz processor. In windoze, the minimum processor speed that gets used is 600 Mhz if I select dynamic scaling in speedswitch xp.

If I boot to FC2 with AC power, klaptop correctly changes the scaling and the minimum cpu frequency will be 600 MHz, as it should be. Setting to max power gives 2Ghz.

However, if I boot from battery power, then the max speed is only 600 MHz when using the performance setting, and using dynamic scaling or powersave, the minimum frequency goes down to 175 MHz as reported by cat /proc/cpuinfo. I believe the cpuspeed reported in /proc/cpuinfo is correct, as programs run very slowly.

The processor speed should not go below 600 MHz.

I've tried chkconfig cpuspeed off, currently /sbin/chkconfig --list | grep cpusp gives

cpuspeed 0:off 1:on 2:off 3:off 4:off 5:off 6:off

but the behavior is the same. Is this a BIOS problem? The only BIOS settings available are to either enable or disable speedstep. With it disabled, the cpu is supposed to remain in the slower 600Mhz state.

I've also tried setting the default governer in klaptop to be performance on both battery and AC, and here is my /etc/cpuspeed.conf

#OPTS="-i 10 -p 10 25"
#OPTS="-a /proc/acpi/ac_adapter/*/state -t /proc/acpi/thermal_zone/*/temperature 75"

Last edited by ashlock; 05-03-2005 at 12:30 AM.
Old 05-17-2005, 03:54 PM   #2
LQ Newbie
Registered: May 2005
Location: Chicago
Distribution: FC1,FC3
Posts: 1

Rep: Reputation: 0
I use
"> kill -s SIGUSR1 <cpuspeed pid>"
to force maximum cpu speed (for my 8600 it's 1.4 G). But this works only when laptop booted on AC powere. On battery boot the highest speed i get is 600 Mhz. The speed never increases above 600 even after i plug in the AC.

Old 05-17-2005, 04:09 PM   #3
Registered: Jul 2003
Distribution: Fedora Core 2, RH 9
Posts: 33

Original Poster
Rep: Reputation: 15
I'll try that.

The max speed when booting from battery power in windoze is 2GHz, and lately I will randomly get a max speed of 600MHz or 2GHz when booting on battery to Linux. It seems that the first battery boot after shutting off from an AC powered state gets the max 2GHz, but subsequent battery reboots get the max speed of 600 MHz.


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Crash when booting on battery power nogdog Linux - Laptop and Netbook 1 11-06-2005 05:52 AM
Laptop Battery Time w/FC2 VinnySem Linux - Laptop and Netbook 8 10-26-2004 09:53 AM
FC2: Wrong sequencing of network cards Schlabbl Linux - Hardware 4 09-02-2004 03:09 AM
cpuspeed 74039186 Fedora 5 04-19-2004 11:17 PM
cpuspeed? Smerk Linux - Software 2 09-09-2003 10:26 AM > Forums > Linux Forums > Linux - Distributions > Fedora

All times are GMT -5. The time now is 12:48 AM.

Main Menu
Write for LQ is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Facebook: linuxquestions Google+: linuxquestions
Open Source Consulting | Domain Registration