The technology exists to allow a G5 PowerBook, says one of IBM's top chip designers.

Norman Rohrer is chief designer of the PowerPC 970FX chip used in Apple's Power Mac G5 desktops and Xserves. He told eWeek: "The same chip that IBM uses for its desktop machines can also be used comfortably within future PowerBook notebooks through a power-management technique called PowerTune."

Industry insiders, though, do not expect such a notebook to ship before the end of the year, but Apple is rumoured to be planning to launch a G5 iMac, which would rely on similar technology, at WWDC tomorrow.