Does Ubuntu automatically underclock CPU in notebooks?

I know in Windows, weather on batter or AC power, if you computer isnt doing any intensive tasks... the CPU is underclocked. You can see this when you right click on my computer and select properties.

BUT... since ive switched to ubuntu, ive noticed my fan is always running at about medium speed, whereas it usually doesnt in Windows. I was told that Ubuntu has The Same power saving features as Windows by users in this forum. Underclocking the CPU doesnt only save power a little, but it keeps down the heat, and since i have a 13.3' laptop this is really important.

So does it underclock? Where are the options? Where can i see the current status of the components in my computer and what they are running at?

Thanks guys

 

open a terminal, and enter the following, then hit enter:

Code:

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq

 

after i pressed enter i got this... dont think it worked

also, if this enables it to auto adjust, where can i check the status? Thanks

 

You don't type a colon in your command there. It just tells you what your current scaling frequency is. If your system is not configured to scale, then that file will not be found.

 

All i typed was exactly what BigV gave me in code. and what I quoted was what it returned. So I guess my system is not configured to scale... so how can i configure it?

Shouldnt this just have been a basic feature of Feisty?

 

no... that was to check that it was scaling...

from everything I've read, it will be scaling automatically... there's actually a GNOME panel applet if you're running gnome which will give you the current CPU speed. right-click on a panel, "Add to Panel" and there's a search field at the top, just search for CPU.

 

alternatively, you could open a terminal and do the following:

Code:

cd /proc/acpi/processor

Code:

ls

this will show you either one or two directories beginning with CPU.

Code:

cd CPUx

(where "x" is a number)

Code:

cat info

I mean, I wouldn't think that the ACPI implementation on your notebook is so broken that this stuff isn't working, but manufacturers do craaaaazy things

 

BigV, thanks for that find. there some neat stuff in there... why cant i find some of those things anywhere else? Anways, when i added the scaling monitor i got this message.

Guess this explains why my fan hasnt stopped.

Then when i entered the code u gave me in terminal this is what i ended up with. (Just for CPU1, i have core 2 duo)

 

strange...

you might also do:

Code:

cat /proc/cpuinfo | grep MHz

/proc/cpuinfo has tons of information, but that command will let you know the current speed of your CPU

you might try going to ubuntuforums.org and doing a search on your laptop model

 

I run Kubuntu Feisty and it seems to auto-scale for me. Normally each core runs at 996MHz, but when I run something CPU intensive, one or both cores runs at 2.16GHz (or, rarely, something in between).

I did nothing to configure it. In Kubuntu, one can get the current CPU status by hovering the mouse over the green and yellow "spark" icon in the panel.

 

Both cores scale in synchronization, of course. Future versions of the processor will scale each core independently, but that's not what currently happens.

 

I get

1000000


Does this mean my distro (SLED 10) is scaliing the cpu freq ?

 

If it's running below the stock speed (whatever yours is) then it is likely being scaled. My P4 runs at 3.06GHz and when I input the command I get:
1867000

 

Miine is a core duo 2ghz cpu.
Does the 1000000 mean each core is running at 1ghz ?
I get the same answer on cpu1

 

yeah... that number is in Hz, instead of MHz or GHz... your CPU is running at 1GHz right now.

 

Both my cores are running at 1.83 Ghz and im not doing anything. That is the speed of my processor (core 2 duo t5600) so my CPU is not scaling. Anyone have any ideas as to how i can fix it?

I cant search forums for my computer cause basically noone has ever hear of it. Its a Chinese brand. Haier W36

Ive got so many problems... i dont know if linux is really worth it

 

I'm running Feisty and it auto scales for me... underclocks just fine.

 

probably the ACPI implementation on your notebook is really broken, then.

you could try searching ubuntuforums.org for other stuff regarding core2duos not scaling.

 

Not according to the Gnome applet I have. It shows the cores throttling separately. They usually sit at 1Ghz, but when I open an application, the first core (CPU0) will usually ramp up to 2.16 while the other stays at 1. I think the advantage of Santa Rosa is that the FSB will be able to throttle between cores and not just the clock speed.

Anyway, if you told us what laptop you have, we could probably help better. Since it's a 13.3", I can make some assumptions that it could be a Sony SZ, Asus W7j, or Macbook. Unfortunately, I don't think any of these work particularly well with Linux, but your ACPI should still be fine.

 

The brand of my notebook is Haier the model is W36. Though it is a chinese brand, it pretty much has all the same components everyother mainstream computer brand has. The only component in here that i havent heard of is my DVD RW. TSSCORP or something like that, but it works fine.

I dual boot my computer with XP. I just restarted into XP and the autoscaling is working fine in there, its underclocked to under 1Ghz. So we can rule out that its not any physically damaged hardware right? I dont know what APCI means... but it works under other operating systems.

 

That model should be fine. You have T2250 and Go 7400, that's pretty standard.
But probably you only have two default freqs, the lowest and the highest(I guess).

 

The ACPI is basically what controls the interaction between your software and hardware. It's supposed to be an open standard, but it is usually reworked to some degree by each individual hardware manufacturer to work specifically with their BIOS and hardware. Therefore, sometimes it doesn't work exactly right with Linux. The problem is that many smaller companies don't look to Linux much when they're making their laptops, they're just trying to get things done as quickly and cheaply as possible, and so they focus all their efforts on Windows. I tried googling your laptop to see if I could find any related information, but the only links I got that weren't Chinese were links to threads on this board.

 

OK - with Ubuntu the things you'll want to check are all in the following directories:
/sys/devices/system/cpu/cpu[01]/cpufreq

So... follow along with me as I do the following from a terminal window:

Code:

$ cd /sys/devices/system/cpu/cpu0/cpufreq
$ sudo cat scaling_available_frequencies
2000000 1667000 1333000 1000000

$ sudo cat scaling_available_governors
conservative ondemand powersave userspace performance

$ sudo cat scaling_max_freq
2000000

$ sudo cat scaling_governor
ondemand

$ sudo echo 'ondemand' >scaling_governor
$ sudo echo `cat cpuinfo_max_freq` >scaling_max_freq

...and then do the same thing in the ".../cpu1/..." directory for your 2nd CPU core.

Now what we did is first checked the available frequencies that the kernel sees. Then we checked out the available scaling governors (how the kernel decides how to set the current CPU frequency) and make sure that it's set to "ondemand" - that is, scale the frequency up when the CPU is under load. Then we make sure that the max frequency supported by the CPU is set under the scaling guideline.

I'm a Gentoo user, so I'm sure that there is some "Ubuntu way" to make sure that the governor is set when you boot. In Gentoo, I just use the CPUFreqUtils userspace program - it sets the scaling_governor to "ondemand" (how I have it configured) on each boot.

 

TSSTCorp is actually more common than you think. My Asus notebook uses a TSSTCorp drive as well. TSST stands for "Toshiba-Samsung Storage Technology" I think, so it's definitely not something "generic" or cheap.

 

Yeah, I meant to say that too. My laptop uses a TSSTCorp drive as well. Most Dell's do, and I think a lot of HP's do as well.

 

notebook_ftw: Thanks for trying to google my laptop, ive tried too. So i just try searching for components and topics now.

Janax: Thanks for posting that code and putting it in such simple terms for me! BUT.... When i enter the code i get this

When i use the GUI to search for that folder, it doesnt exist under CPU 0. But then i checked CPU1 anyway, and it did have the cpu scaling folder and this is what i got...

So is it not letting me change it from "performance" to "ondemand"?
And should my CPU0 also have the CPU Frequency folder? Can I just copy and paste the folder from CPU1 to CPU0?

About the TssTCorp... ok.. well then i guess it is pretty common, so i have a chinese brand laptop, with all the components of any other computer which = a lot cheaper but comes at the price of compatibility becuase they manafacture quickly to only support windows?