Comment 3 for bug 135356

This _might_ be related to bug no. 11561, https://bugs.launchpad.net/ubuntu/+source/evms/+bug/115616 . I had the same problem with the cpu always being full-on. This is because of a problem with evms.

sudo aptitude remove evms

in a terminal solved the problem for me.

In a terminal, type

dmesg

If the output from dmesg shows lots of lines like this:

[ 2860.300000] device-mapper: ioctl: error adding target to table
[ 2860.300000] device-mapper: table: 254:0: linear: dm-linear: Device lookup failed

then evms is likely to be the problem, and it does not have to have anything to do with acpi. Try the above command and see if it helps.