This is a DC-IN board for the G4 Aluminum Powerbook 15". This is the board that the power adapter plugs into. If you're having power related issues with a connection at the power adapter, then there is a good chance this board may solve the problems. There are a few versions of this part. Please make sure you choose your correct version from the drop down box. *NOTE - The 1.67GHZ Board looks slightly different than the picture above! Choose your Mhz speed from the drop down box below to ensure you receive the correct piece for your model.