[CentOS] acpi for Intel p45 chipset (C2Duo)

Thu Dec 17 18:38:24 UTC 2009
Mr. X <tlviewer at yahoo.com>

Hello,

First time I install Centos (5.4) on a consumer Intel Motherboard. I've done 5+ AMD (am2 form factor) installs.

The MB is Gigabyte ep45-ud3r with a CPU:Intel LGA 775 E7600 wolfdale

I cracked the lm_sensors nut with 2 modules and lm_sensors from elrepo. The modules were
   kmod-coretemp
   kmod-it87

Now I'm trying to get cpuspeed to behave, or at least understand what it's doing. Here's my bios objects
------------ snip dmesg---------
$sudo dmesg | grep state
ACPI: CPU0 (power states: C1[C1] C2[C2] C3[C3])
ACPI: Processor [CPU0] (supports 8 throttling states)
ACPI: CPU1 (power states: C1[C1] C2[C2] C3[C3])
ACPI: Processor [CPU1] (supports 8 throttling states)
---------- unsnip ----------

In the advanced bios menu I enabled all the switches for CPU state management. If not enabled there is no acpi.

My CPU is OC'ed to 3.74 Ghz
The Intel state management hands it off to the kernel with max frequency of 2.8Ghz but bogoMips is unchanged and reflects OC'ed value. There are supposed to be 8 throttling states, but acpi-cpufreq (driver) only uses 3 states (1.6 Ghz - 2.8 Ghz).

Has anyone found another driver to work better? I tried
  speedstep-centrino

but it refuses to load. There is also p4-clockmod too, but I had doubts about it. Is this the best I can do?

So far benchmarks are very good and the acpi power management does not hurt them. 

-- 
Mark