Apple’s new “Double for nothing” PowerBook promotion, which doubles the RAM the systems ship with, may not benefit some customers. The 667MHz model, which ships with 512MB of RAM as a result of the promotion, does so using two 256MB memory modules, not a single 512MB memory module. As the PowerBook G4 only features two memory slots, users looking to expand the system’s RAM beyond 512MB will be forced to remove one of the two modules, essentially negating the promotion.