I have been trying all sorts of things to try and get my CPU throttling working (I had it a while back but I think I re-installed) and had almost given up.
I tried one last time removing all power controlling stuff apart from that which would have removed KDEbase etc. Rebooted and added the software listed below and rebooted again.
I am running KDE upto date 4.6.5-1 and kernel 2.6.38.7-pclos1.bfs #1 SMP PREEMPT running on a Asus M4A78LT-M LE AMD 760G Socket AM3 quad core with Integrated ATI Radeon 3000 2 Gb RAM
For those of you wanting to save some energy here are the programs that worked for me
Installed software
acpid, libpowersave10, pm-fallback-policy, pm-utils, powersave
Widgets
I added system load viewer and that shows me it is working. I didn't have to do any setting up.
Hope this helps