Cx states not working on Dell Inspiron 8600 (Pentium M)

Ulrich Spoerlein q at
Thu Aug 26 11:10:12 PDT 2004

On Thu, 26.08.2004 at 09:37:33 -0700, Kevin Oberman wrote:
> The cx_usage is limited to C1 or C2 if USB is loaded. It's polling of
> the bus for changes prevents the state from dropping to anything really
> useful. If you don't always need USB, build a kernel without it and load
> it as required.

Ah, that explains it then. Is there anything that can be done about
that? Does that mean, that even Windows is not using C3 and C4 if there
is a USB mouse plugged in?

> What do you have in your rc.conf? The default for economy_throttle_state
> is "HIGH" which is probably not what you want. Not knowing how fast your
> CPU is or how you use it, I don't know where you want to set it.  
> Try experimenting with:
> sysctl hw.acpi.cpu.throttle_state=n
> setting 'n' to values in the range of 1-8 and see where you think it's
> reasonable to get work done without draining the battery. I use:
> economy_throttle_state=4. Any lower and things start to get painful for
> me. 

Ah, I thought this was a dynamic setting, meaning that I change it to a
"wanted" value and it adjusts itself, depending on if there is work to
do or not.

I'm using colin's est.ko and estctl and it is working very nice, but it
doesn't give me the battery lifetime or temperature level that Windows
does. What else am I missing then, to get the same cool temperature as
in Windows?

(Sorry for always comparing to Windows, it's just that there's
noticeable difference to FreeBSD in that regard.)

Anyway, thanks to you and Nate for the explanation. I should have
thought of reading acpi(4) first.

Ulrich Spoerlein
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