My powerbook won't sleep. When its supposed to go to sleep the screen turns off yet the computer still runs and the fan turns on. To test I set my computer to sleep after 1 minute and I unchecked the box that turns of the LCD after a certain amount of time. The only way to make the computer sleep is to shut the lid, go under the apple, or press the powerbutton and then sleep. I have called apple support when this happened first, about 2 monthes ago. I went through a bunch of things like resetting the PMU and the only solution was to reinstall the OS (I'm running 10.3.9 and I'm all up to date). I've done it three more times since that event and the problem keeps on coming back about a week after I reinstall. I've even tried not installing printer drivers but still, the problem occurs. None of the sharing settings are turned on either. I don't have any 3rd party programs that would interfere with the auto sleep. I hate walking away from my computer when it has 90% battery life and coming back a couple hours later and its down to 45%. I also don't want to keep on spending hours reinstalling the OS. I'm really frustrated right now and before I call Apple again, and potentially start to get even more angry, does anyone know what is going on here and what some solutions could be. EDIT: I forgot to say. The problem ususually starts with the sleep light not working and progresses to the state where it won't automatically sleep.