I have a ibook G4 that's been randomly shutting down. It started doing this maybe about a month ago but it's started getting really bad lately. At first it would shut down if I unplugged the adapter. Not every time I unplugged it, but probably about 50% of the time. When I press the battery button all of the green lights would light up. About half of the time it will start up again if I just hit the power button but the half of the time I have to reset the pRAM. Lately this same thing has been happening except when the computer is still plugged in. And when in say shutting down I mean essentially instantaneously. One second it's on and then the screen goes black and it makes that turning off noise. Not a chime, but like all the fans and hardware are coming to a stop. Any help would be greatly appreciated. Thanks!