A quote from <http://docs.info.apple.com/article.html?artnum=88231>: "The 65 W Apple Portable Power Adapter is used with the PowerBook G4 (1 GHz/867 MHz) computer. It also works with computers that use the 45 W adapter. The AC cord for the 65 W adapter cannot be used with the 45 W adapter, however." I believe that if you use the 45W adapter with a computer that shipped with the 65W adapter, the battery may or may not charge, and it may even draw some power from the battery if the power adapter can't provide enough power. "Jeffrey K. Lew" <jklew at ucla.edu> writes: > Isn't it the other way around--the AC adapters for Rev. A G4's can't > be used optimally with later versions because they don't put out > enough power? I would think the only problem with using the newer > adapters with Rev. A G4's is that the light-up plug might not give > the correct indication because the Ti 400/500 current draw is less > than the later models. Kynan Shook kshook at mac.com http://homepage.mac.com/kshook/index.html