[ltp] ibm r40 2722 cpu cooler running even when idle and battery runtime

[flokno]

hello all!

i own an ibm r40 2722, pentium m 1.5 ghz.

kernel=2.4.22-ac4 with enhanced speedstep and apm enabled. acpi still
seems broken. i also use cpudynd as a userspace daemon.

when i let the computer switched on for a longer time (maybe 10 minutes)
the cpu cooler starts to blow about every 5 minutes for 40 seconds even
though the cpu is at 600mhz then.

the behaviour is the same when on battery or on a/c.
but when using windows xp the cpu is quite all the time when idle.

what can i do to keep my cpu fan quite under linux too?

another point is that my runtime on battery is only 3:10 hours compared
to 5:something hours when in windows.
so it doesn't seem that the cpu is completely speed stepped down. (or
voltage is lowered?)
i also want to have these 5 hours under linux...
the two problems seem to be dependend somehow.

maybe somebody knows any hints for my problems with this particular
laptop!

thanks in advance, 
 flo