I installed Linux Mint 15 on my Macbook (1.8 ghz 4g RAM core 2 duo) and bought a new battery. However when I run it unplugged I get critically low battery warnings even at 96%. It says I have about 1hr 45mins on a 100% battery and I can watch it drain. To investigate I installed powertop and to my dismay the cpu usage at idle is 90% or more. It lists 3 cpus - one at 0%, one at 1%, and the last at 90-95%. Even using the "tunables" and shutting down almost everything, it still idles at 90-95%. Any ideas? Maybe a different flavor of linux? I would be down with that, I just need some advice.