Need serious help with Dell D600 Latitude laptop and Power Management please :)

[Kevin Oberman]

> Date: Mon, 20 Feb 2006 09:51:43 +1100
> From: "Dave Symonds" <dsymonds at gmail.com>
> Sender: owner-freebsd-stable at freebsd.org
> 
> On 2/20/06, Ryan R <air.lightz at gmail.com> wrote:
> > I am running a Dell D600 Latitude laptop (2.0ghz Pentium Mobile) and
> > dual-boot Windows.  In Windows, I get about 3 hours and 30 minutes roughl=
> y
> > of battery time when I am not plugged into the AC Power, but in FreeBSD I
> > get around only 1.  In Windows, my fans don't generally run until the sys=
> tem
> > is doing something full load, and runs very cool.  Here in FreeBSD, my fa=
> ns
> > are running FULL SPEED all of the time and also seems to be hotter than m=
> any
> > conventional ovens.   It is definitely way hotter than it is in Windows, =
> and
> > definitely isn't relaxing when the system isn't doing anything stressful.=
>   I
> > am a novice user and don't know where to start in solving this problem..
> > How come it isn't working automatically :(  Are there going to be alot of
> > manual commands I have to enter just to get it to calm down?
> 
> I'm running -STABLE on a Latitute D800, so I can sympathise. It took a
> fair bit of reading and poking around, but I found this to be a good
> start:
> 
>     * Add these lines to your /etc/rc.conf file: (options are detailed
> in powerd(8))
>             powerd_enable=3D"YES"
>             powerd_flags=3D"-a adaptive -b adaptive -p 2000"
> 
> That will probably get you a long way there just by allowing the CPU
> to slow down during inactive periods. Don't ask me about getting the
> darn thing to suspend, though. Every time I've tried it has failed to
> come out correctly. And keep in mind that there is no suspend-to-disk
> support (called "Hibernation" in Windows) for FreeBSD.

There are many things that can help.

First, I don't see a reason for "-a adaptive" on powerd. If you are
plugged in, why cut performance?

Try "sysctl hw.acpi.cpu" and see what values you have for cx_lowest while
on battery. It should be the largest "C" value available, usually 3C43
or C4. This is very significant. To change this, use the following in
rc.conf: 
economy_cx_lowest="LOW"
This is now the default in -current, but that change has not gone into
anything else.

If you can run without USB, take it out of yo9ur kernel. It will keep
your system way to busy, even if nothing is plugged into any USB port.

There are probably things I have missed, but these are big ones.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634