I am using an Acer Aspire 1200 - rather old, but ACPI is implemented.

My problem is, that the fan is always running, and the temperature is always at about 50 degrees Celsius.

cat /proc/acpi/processor/CPU0/info

says

processor id: 0
acpi id: 1
bus mastering control: yes
power management: yes
throttling control: yes
limit interface: yes

The very interesting thing is that the active state is ALWAYS C0, never any other, but usage of C2 is counted up rather quickly - what is wrong? Besides, there is never an asterisk "*" beside any of C1 or C2 (C0 is never listed, but this is as documented).

cat /proc/acpi/processor/CPU0/power

active state: C0
max_cstate: C8
bus master activity: 00000000
maximum allowed latency: 8000 usec
states:
C1: type[C1] promotion[--] demotion[--] latency[000] usage[00001722] duration[00000000000000000000]
C2: type[C2] promotion[--] demotion[--] latency[020] usage[00283115] duration[00000000010934602140]

Any ideas?
thanks in advance.