My processor is an AMD quad-core Athlon II 640 Propus rated at 3.0 GHz. It is in an ASUS M4A88TD-EVO mother-board.
I am using openSuse 11.3 as my OS. When I open “My Computer” it correctly identifies the CPU but lists the speed as 800 MHz at times and 3,000 MHz at other times.
Does the computer somehow idle down the processor when it’s not busy? Or is there something else going on?
Yes, modern processors can be throttled by software to save power when the grunt is not needed. Read about the powersave daemon.
In addition to reading about the Powersave daemon as ken_yap correctly suggest, I might suggest you visit the settings in the Personnel Settings application. To get there open your KDE menu / Personnel Settings / Advanced Tab / Power Management. You select Edit Profile on the left, select the profile you normally use in Profile Management and then select the CPU and System Tab on the right. If you should upgrade to KDE 4.5 (the default is 4.4), CPU speed management has been moved to YaST, so ask about that if this is true.
Thank You,
Also you might like to install the powertop program which can profile your system and tell you what processes are waking the CPU most often. It can help you increase battery life.
To display information about cpu frequency scaling, you can install the package “cpufrequtils” (using YaST or zypper). Then you can run the terminal command “cpufreq-info” (as normal user). For example it displays this for my Intel Core2Duo T6670 processors:
cpufrequtils 006: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to http://bugs.opensuse.org, please.
analyzing CPU 0:
driver: acpi-cpufreq
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 0
maximum transition latency: 10.0 us.
hardware limits: 1.20 GHz - 2.20 GHz
available frequency steps: 2.20 GHz, 2.20 GHz, 1.60 GHz, 1.20 GHz
available cpufreq governors: conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 1.20 GHz and 2.20 GHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 1.20 GHz.
analyzing CPU 1:
driver: acpi-cpufreq
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 1
maximum transition latency: 10.0 us.
hardware limits: 1.20 GHz - 2.20 GHz
available frequency steps: 2.20 GHz, 2.20 GHz, 1.60 GHz, 1.20 GHz
available cpufreq governors: conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 1.20 GHz and 2.20 GHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 1.20 GHz.
You can also see which cpu frequency related modules you have loaded, with the following terminal command:
lsmod | grep freq
OK, thanks all. I didn’t know computers could do this. It just kind of confused me when I noticed it running at 800MHz and then when I checked again it was back to 3 Gigs, then back down to 800. I know this computer sure runs a lot better than my old Duron 800 ever did, back in the day.
You can also see the CPU core frequencies in near real time if you open up under the K-menu icon, the System Monitor.
Direct command
ksysguard %U
There you can open a new tab under File and then select
and drag it from the Sensor Browser into the new tab and select line graph.
Repeat this for each of the other CPU’s and drag over the top of the CPU1.
If you stick with the defaults this will show the history of all core frequencies for the last 30 seconds.