Powerbook G4 15in Battery, how long do they last?

Anna F

Hi i've just got a powerbook and want to know how long the battery lasts in average use. I have it on the better battery performance setting but I'm sure my battery isn't lasting any longer than 2.5 hours. is this normal? i've done the whole thing it says in the manual about calibrating or whatever but it just doesn't last long.
Are my expectations for the battery life too high? or is there something dodgy with my battery?
(it's not one of the recalled batts)
I usually get about 3 - 3.5 hours with my Albook .. but that's if I'm really not doing anything other than surfing the web or coding or reading...

Playing music will drop the battery life considerably... movies even moreso, same goes for compiling (obviously).
2.5 hours on most aggressive cpu settings and screen at the full brightness are kinda ok. Of course it all depands on what you are doing.
Set your settings to 'Better Battery Life' and see, if you can get more than 3 hours. Another hint: adding more ram will not only make your system snappier but also last longer on battery. The more ram the less swap and less hard-disk activities.
Btw, playing music at reduced screen brightness does not stress the system and will actually cause a longer battery life. 3d games are very heavy for your system and make your battery last very short.
If you have an Airport card or bluetooth try turning that off if you are not using it. Also non-self powered USB devices or FireWire devices reduces the life time of the battery.

The average of the battery life is actually arround 2.5 and 3.5 hours.

There is a tip to get info about the status of your battery. Open /Apps/Utilities/Terminal and type

% *ioreg -wo -l | grep Capacity
Thanks for the responses. I took it into the apple shop today to ask them to check the battery and they've taken my laptop in for further testing because one of the guys saw the percentage drop quite fast depsite hardly doing anything to it. He even said 2.5 hours doesnt sound right especially if im not really doing thing that pushes the computer.

Well i hope the discover that it's just a battery problem, coz if it's the laptop itself I'm demanding a full exchange!
Turn off bluetooth and AirPort when not needed. Use Energy Saver to higher performance. And with a 15" PowerBook (same for 17), you can hot swap batteries. Just but the PB to sleep, pop out the old battery and put a second one in and open it up.