On Wed, Dec 29, 2010 at 11:13 AM, Bill Longman <bill.long...@gmail.com> wrote: > A strangeness I have noted is that /proc/cpuinfo has this for its power > capabilities: > power management: > Nothing.
FWIW I have Core i7 920, and it also has nothing in the power management in cpuinfo, but CPU frequency scaling does work and speeds change (using ondemand governor, in a desktop machine). $ cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_* 2661000 2660000 2527000 2394000 2261000 2128000 1995000 1862000 1729000 1596000 conservative userspace powersave ondemand performance 1596000 acpi-cpufreq ondemand 2661000 1596000 <unsupported> So it seems similar to yours except that your max_freq and min_freq are the same! Which matches what you say about it never going faster than the minimum speed. In kernel docs Documentation/cpu-freq/cpu-drivers.txt there is some information about how the min and max speed are set by the policy that is in use (by whatever driver is controlling the scaling). So I don't know if there is a userspace program (like KDE laptop stuff) that might be overriding with its own faulty settings? Seems like your kernel settings are probably okay since you can see all of that so far. If you run powertop can it see all of the C-states and P-states without any problems?
