When I set my energy saver mode to highest performance, I only get a 2 min advantage over a setting such as DVD playback. You would think there would be a much larger gap. Also, at full charge, my iBook only says I will get along the lines of 3.5 hours of life. This is a new iBook. Shouldn't the battery life be longer for such a little thing that does nothing intensive and only acts to type notes?