Apple's M9321G/B Mini DVI to DVI Adapter is designed for use with the iMac (Intel Core Duo), MacBook and 12" PowerBook G4. Connect the adapter to the Mini DVI port of the computer and the DVI end of the adapter to an external DVI monitor or projector. You can also use it in combination with the optional Apple DVI to ADC Adapter (available separately) to connect your computer to an older display with an ADC connector.