Which Power Adapter is the correct one for Powerbook G4 15inch FW800 - 45watts or 65watts I have a Powerbook G4 15inch FW800 with a 45watts Apple style power adapter. Recently it would not boot up. I removed the battery and it did. However after a shutdown, later on it did not boot up without battery. Only after I reinserted the battery and after waiting for a few minutes did it boot up again. I heard that I should use a 65watts Power Adapter and not a 45watts. However, when I search for a power adapter based on my Powerbook's Apple Order number: M8981LL/A and/or the Model Number: A1046 - I sometimes get a match with a 45watt adapter and other times with a 65watts adapter. So, which adapter should I use with my Powerbook?
In practice, I've never seen a properly working 45 watt adapter not be able to boot a properly working PowerBook when you remove the battery.

The 45 watt adapter was intended for smaller devices and would often not be enough to both charge and run a 15 inch PowerBook in all situations even when everything was working properly.

At this point, with ten year old equipment, it's possible you will need a 65 watt adapter or have some power management issues with the adapter or the Mac.

That Mac should have a 65 watt adapter for best results, power on and charging since the G4 and battery do need that much power to work as designed.