ThinkPad T61P Speed Problems on 13 Feb 2008

[james.he...@gmail.com]

If you aren't already on the latest BIOS, try upgrading.

The ACPI tables in the BIOS can control the maximum speed of the CPU,
and Linux respects those values these days (exceeding the ACPI speed
maximums can damage certain hardware). Of course, there is the
possibility for the ACPI tables to be buggy and incorrectly limit the
CPU speed, which is why I suggest checking for an update.

James.

[Diego Escalante]

Work around it by asking g-p-m to keep maximum power saving always.
Seems to me like your cpufreq is upside down.

[pedromj]

I think that your problem is related to activity. To prevent burned
processor, it forces to step down to the minimum frequency. As you
say, it is not real hot but your system can think (bad) that the
processor is arriving to its temperature limits.

¿Did you tried to boot with "acpi=off" kernel parameter?

Your new laptop's ACPI could be buggy. You can take a look to the DSDT
tables (/proc/acpi/dsdt). Copy that file, run "iasl -d" to decompile
and then run "iasl xxxx.dsl" to recompile. Take a look to the warnings
and/or errors.

If that command output errors you can try to fix them, recompile and
tell your kernel to load the fixed DSDT table.

I hate that manufacturers don't follow hardware specifications. Lenovo
(inherited from IBM) always had good compatibility but now, who nows.
ACPI behavior in Linux is very hard to get 100% working, normally due
to Microsoft ACPI compiler.

Best wishes,

Pedro

[pelayos...@gmail.com]

If you use a live CD from other distribution (say Ubuntu), does the
problem persist? Just to see if it's a general hardware/Linux problem
or something specific to your configuration.

[Miguel de Icaza]

Hello James!

If you aren't already on the latest BIOS, try upgrading.

I just updated my BIOS, but it continues to have the same problem.

Am going to try today to downgrade my kernel to the last working version and see if that helps.

[Gustavo Rubio]

You could also try to lower the shutdown/change frequency temperature
on the bios... if that option exists of course.

There are some bios'es that have these options where you can set how
high the system will go until it shut downs itself. I dont know if
this option is available on laptops, but I have seen it in desktops
and some people have low values (like 40C) and when they start doing
something CPU-Hungry like playing games or compile something then the
system gets warmer and shuts down itself. Maybe you have something
like that so the bios lowers the cpu speed in order to get the system
cooler.

[Adam Williamson]

As I sent via email - just unload the cpufreq module. lsmod | grep
cpufreq should find it, then you can unload it and blacklist it.

[abac...@gmail.com]

I just noticed and have been fighting the exact same problems for the
last couple days... and its extrememly frustrating!

I even went as far as to completely wipe and reinstall ubuntu :-( but
that didn't fix the problem

No clue on why they're happening, or what to do to fix them, but
hopefully a fix will surface!

initially I thought it was a temperature related problem, as when I
watch the gnome-sensors applets the processor speed gets pushed down
for a while to 1.2Ghz when the temperature reatches around 60degrees
celcius. It then sits there for a while at 1.2Ghz before jumping back
up to 2.2.

however after watching it more it seems somewhat random, and unrelated
to the temperature as it will drop down at seemingily any temperature,
although maybe its a flakey sensor, and it thinks the temperature
spikes, which forces it back down into a "safety" mode.

all throughout though, the fan seems to just hum along at 3000 RPM.

anyway, I really hope you/someone else is able to fix this!

please let me know if you do!
thanks,
-=Abe

[abac...@gmail.com]

Not sure exactly what was the step that fixed things, but things are
now working for me! :-) (i tried to comment earlier saying I was
having the same problem, but it looks like it hasn't shown p)

here's what I did:

when I noticed the problem I had been having other driver issues from
installing the newest iwlwifi drivers from source, so I decided to
just do the "windows fix" and wipe everything, and reinstall :-P

however when I got things back to running, it seemed to not have fixed
the CPU frequency issue.

I then went into windows (its dual booted) and installed a bunch of
updates from lenovo, including the latest bios: (2.10-1.08)

I then tried to test to see I saw the same problems in windows, but
didn't see the problems. This made me hope that the bios update had
fixed things, but when I got back to ubuntu I was still seeing the
same problem.

none of the above fixed the problem, but they may have been necessary
precursors???

finally, I decided to try disabling speedstep in the bios, and see if
linux behaved then... fortunately it did! when I booted into ubuntu it
popped up a notice about not being able to change/set the CPU
frequency, and happily ran at 2.2Ghz.

I then decided to try re-enabling speedstep, and set everything in the
power options in the bios to maximum performance, for both the CPU
speed settings, and the thermal management and once again things
worked. (not at all sure if this is relevant, but this step was done
on battery power :-P)

Finally I decided to try going back to the original settings of
maximum performance while on AC power, and battery optimized when on
battery power... and things still seemed to work.

when I finally got home, I plugged back in again, and things continue
to work :-)

my cpu has been chugging away at 100% on both cores for the last half
an hour, and its staying at 2.2Ghz like it should :-)

so anyway to sum up... no idea which step actually fixed things but
things I think may have been relevant:
update to latest bios
disable speedstep in the bios, and boot into linux
re-enable steedstep and put everything to max performance
put back "battery optimized" settings

no idea if doing the steps on battery power was relevant, but thats
how it was when I did.

good luck!!!
-=Abe


On Feb 13, 11:59 am, "Miguel de Icaza" <miguel.de.ic...@gmail.com>
wrote:

[abac...@gmail.com]

My computer started acting up again out of the blue this afternoon :
( No clue why, it was running at 2.2 Ghz all last night and this
morning, both on battery power, and while plugged in, and everything
seemed fine.

then this afternoon I noticed it was running at 1.2Ghz, and wouldn't
go higher again.

One really weird thing that I've noticed is that everything seems fine
when I unplug the laptop, and have it run on battery power.... If I do
that it will run at 2.2Ghz just fine.

For now I'm just gonna disable CPU throttling, but hopefully someone
can figure this one out!

thanks,

-=Abe

On Feb 13, 11:59 am, "Miguel de Icaza" <miguel.de.ic...@gmail.com>
wrote:

[D. Moonfire]

I'll mention a completely obsucre reason I had my CPU driven down: cats.
It was for a Dell, but I couldn't get my computer to go higher than 50%
power less than 10 minutes after the machine. What happened was my cat
sits on my laptop and her hair got jammed into the intake fan. So, I had
to pop off the keyboard and unscrew the CPU to pull out this huge wad of
cat hair that jammed itself into the cooling grills by the CPU. :)

But, that said, it is sometimes a good idea to use the hardware testing
stuff (on its own partition on the Dell's) to see if the fan is actually
working properly (i.e. running AND producing air flow).

Cheers!

[abac...@gmail.com]

so after playing around some more, I believe the culprit is the
"underpowered" 65watt travel charger, or some side effect of using it,
because when I use the 90watt stock that came with the laptop, things
seem to work fine.

good luck!
-=Abe

[Miguel de Icaza]

Hello,

I have had the exact experoience: sometimes things seem to work for a
while, and I claim victory, just to found out after a reboot or so
that the machine starts acting up again.

Same exact symptoms that you experienced