There are other useful kernel options, all listed there: 
http://www.linuxpowertop.org/faq.php

For your extra time interrupts problem, you may want to look if HPET is 
enabled on your system: 
  cat /sys/devices/system/clocksource/clocksource0/available_clocksource
  (or grep hpet /proc/timer_list)
should show the word "hpet", and if NMI watchdog is off :
  cat /proc/sys/kernel/nmi_watchdog
should be 0.
-----------------
cat  /sys/devices/system/clocksource/clocksource0/available_clocksource

should show something like:

tsc hpet acpi_pm jiffies

Boot argument boot be:  clocksource=hpet

------------------


#!/bin/sh
echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo 1 > /sys/module/snd_ac97_codec/parameters/power_save
#iwpriv eth2 set_power 5
echo 1500 > /proc/sys/vm/dirty_writeback_centisecs
hdparm -S10 /dev/hda
/bin/mkdir /var/log/munin/
/bin/mkdir /var/log/lighttpd/
/etc/init.d/munin-node restart