is there notebook hardware control for linux

or any program to under voltage and monitor CPU speed and temperature?

 

you can monitor with lm_senors and their front-ends, also, there are some ways to undervolt certain cpus with kernel patches, check out the gentoo forums/guides/faqs.

regards,

//m.

 

https://wiki.ubuntu.com/UndervoltingHowto

 

Undervolting only available in Intel based CPU using Linux-PHC patch.

 

hmm what about core 2 duo on Ubuntu 7.04?

 

I thought core 2 duos had a hard-set floor for the voltage of the lowest speed step?

wouldn't that make undervolting kinda pointless, given how little the computer actually uses the "full throttle" cpu frequency

 

They're locked to .950V on lowest settings. Programs wont get it any lower.

 

EmiFreq-Applet works very well for me. I get to see my CPU temp (in both F and C) and control how throttled the CPU is.

 

So... Can you under volt a C2D in linux? What I want to do is run my CPU at .950 regardless of the speed. I've been doing this in windows no problem for about a year now. *kicks RMclock for not porting to linux *

 

i dont have C2D yet. My X61s is coming in few weeks. I sure hope Ubuntu will be able to under voltage C2D in Bios or something.

 

undervolting is available only through kernel patching in linux afaik, if at all for c2d (most guides only mention p-m, max cd i think?). c2d's are afaik hardcoded.

why would one want to undervolt their machine anyway, it's not like the cpu's nowadays aren't power efficient... it's the lcd screen and hd's that drain the power the most, afaik.

regards,

//m.

 

C2D's aren't locked, you can use both RMclock and NHC to do it in windows. The reason I want to under-volt is for cpu temperature. Anyways, this isn't a why thread, this is a how. Thanks for the info I'm going to look into the kernel patching.

 

https://wiki.ubuntu.com/UndervoltingHowto#preview
http://ubuntuforums.org/showthread.php?t=146366

I don't know if you've actually found some stuff, but you might want to try there for a start.

 

Thanks for the information BigV (+rep)

 

I'm aware it's not an if thread, but when the there's a why arising about a how, I find it useful for others possibly to ponder that option.

Anyway, http://www.google.com/search?q=undervolting+c2d+linux&ie=UTF-8&oe=UTF-8 points us to nowhere else than nbr forums (third hit from top in my case, http://forum.notebookreview.com/archive/index.php?t-92618.html ) where they claim it's the same for c2d and pentium-m with linux patches.

Btw, I guess it's not that wise to pass someone a rep point for repasting the same links that were already pasted before in the same thread, no that I'm grumpy for not recieving one, but if at all you ought to perhaphs take a rep point off of your list for not carefuly reading the thread

Anyway, if you manage to get it running, whip up some faq maybe or corrections to the faq's already available (there's a gentoo undervolting faq too, http://gentoo-wiki.com/HOWTO_Undervolt_a_Pentium_M_CPU ) and actual results. Wouldn't mind getting off 5-6 degrees celsius off of the cpu had it taken down the fan noise, and not caused any (noticable) performance loss.

Because these guides are for single-core pentium-m, it could be that there might be some synchronization needed for dual-core cpus like c2d or cd, that would switch voltage on both cpu cores simultaneously, dunno how that works and if it could cause some instability if say one core has been undervolted and the other has not yet been so. I guess you could always hard code the values in kernel for that, less flexible that way but probably would work had the userspace approach worked not.

Also, the patches used here (in the mentioned guides), the phc patches, patch speedstep-centrino, which you shouldn't be usng anyway. You should be using acpi-cpufreq because afaik it incorporates speedstep-centrino's abilities PLUS it can do nothing else than control voltage on a cpu to lessen power usage further Although it's done reasonably automatically, and probably could need some tweaking for best results on a particular box, If at all the voltage interface works, this is information I have not yet confirmed myself, as I've only read/heard about it somewhere when I was choosing my cpufreq driver a while ago.

Also, looking through the internet just now it seems there is a significant gain in temperature/power dissipation with undervolting without much, if not any, performance loss. SO very interesting indeed, please post some results if you sort it out! I got a t5500 too if your signature is up to date, and would always be interested in less degrees for the fans to stay silent Also less voltage,less power, possibly longer life-span for cpu I reckon?

Regards,

//m.

 

I gave you +rep for that answer... =P

I'll deal with it later.. right now I'm fighting with BF2142 running in linux...

I was hoping there was something more like a parameter I could pass somewhere, or a config file to tweak..

 

Nope. That might be interesting, though. Might be something to hack into the kernel. The problem is that it's very hardware dependent. It won't work for a P3, or a P2, but the kernel is still virtually the same on those machines. So they basically just don't have the patch in the kernel because it won't work on most machines. From my understanding, at least.

 

But Marrrrtttyyy.... You're just not thinking Fourth Dimensionally!!
-Doc Brown..

 

Linux-PHC is used for undervolting P-M's. Core Duo is partially supported, the problem is that the they use different codes for the voltage so you have to be careful as setting a voltage meant for the P-M will result in a different voltage for a Core Duo. I assume this is the same for most Core 2's because they use the same socket.

 

P-Ms, CDs, and C2Ds use a bunch of different sockets, but all of them happen to have 478 pins.