In order to provide desirable features of a low power personal digital (PDA) and a powerful computing personal computer (PC), the PDA and the PC are combined as one integrated computer architecture. When low power consumption is desired, the PDA controls the computer architecture, and when increased computing power is needed the PC is given control of the computer architecture. To maintain portability feature of a small size PDA a removable or detachable PDA is integrated into the chassis housing the computer architecture. The PDA is housed in a package that may be placed in an expansion bay or connected to the exterior of the chassis. The PDA has its own separate memory, input device, display and battery so it can operate independently. Interface connections are provided on the PDA in order to connect to the computer architecture.