Comment 23 for bug 93331

Same here: frequency scaling not working, neither by acpi-cpufreq nor speedstep-centrino.
Notebook Maxdata 8100X (PentiumM 1.6GHz) ICH4

cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 13
model name : Intel(R) Pentium(R) M processor 1.60GHz
stepping : 6
cpu MHz : 1593.583
cache size : 2048 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 2
wp : yes
flags : fpu vme de pse tsc msr mce cx8 sep mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 ss tm pbe up est tm2
bogomips : 3189.32
clflush size : 64

what is maybe more important:
sudo modprobe acpi-cpufreq
FATAL: Error inserting acpi_cpufreq (/lib/modules/2.6.22-14-generic/kernel/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.ko): No such device

after that, in dmesg:
ACPI: Invalid _PSS data: freq is zero

sudo modprobe speedstep-centrino
FATAL: Error inserting speedstep_centrino (/lib/modules/2.6.22-14-generic/kernel/arch/i386/kernel/cpu/cpufreq/speedstep-centrino.ko): No such device

nothing in dmesg after that.

for dmesg output, please see:

https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.22/+bug/152445

with BTW seems to be duplicat of this bug