Comment 58 for bug 183033

Hi all,
I had the same problem on Dell Vostro 1500, Core 2 Duo. After resume, CPU1 was stuck on 1994 MHz and there were analogous ACPI error messages in log. I tried newest BIOS, switching CPU1 off --- without success, but finally I found a workaround at:

http://gnugeneration.epfl.ch/users/fasnacht/d630_cpufreq

Briefly, the problem is probably in the acpi-cpufreq module. If you remove it before suspend (by force: rmmod -f) and insert back after resume, frequency scaling works ok for both cores. Of course, acpi-cpufreq has to be compiled as a module (which is likely with distribution kernel) and you should stop your cpufreq/power daemon first. I know nothing about *buntu (using gentoo), but this can help you too.

Btw. 1994 is the default frequency, which my C2D starts at without any cpufreq support.