The PowerBook 100-series has a single motherboard expansion slot addressed along a 16-bit memory bus. This computer requires unique 100ns pseudostatic RAM modules (PSRAM) in either 2MB, 4MB, or 6MB capacities, as it typically shipped in a 2MB default configuration with one vacant expansion slot. Former Apple Technical Information Library (TIL) article PowerBook 100: RAM Expansion Card Compatibility 8/92 noted that the PB100 "requires additional signal lines on the memory card to do addressing correctly," not to mention the key fact that the physical form factor of third-party memory modules commonly used in other 100-series PowerBooks is often incompatible. When ordering PSRAM for this PowerBook, please mention the model number in the Comments field of the order form.
With 2MB PSRAM soldered to the logic board, the PB100-series is bootable out of the box. The addition of a single 2MB, 4MB or 6MB expansion module yields memory configurations of 4MB, 6MB, and 8MB. The maximum amount of usable memory in the PB100-series is 8MB, in the form of a single 6MB module in combination with the soldered 2MBs of logic board PSRAM.
This motherboard, based on the Motorola 68HC000 processor at 16 MHz, supports twice the maximum memory of other Motorola 68000-series Macs due to differences in ROM, despite the fact that it addresses PSRAM along a 16-bit data path rather than the 32-bits characteristic of the Motorola 68030-series.
Specifications Logic Board PSRAM 2MB. Supported Modules 2MB,4MB,6MB. Number Expansion Slots One (1). Supported VRAM None. Number VRAM Slots None. L2 Cache Supported None (Non-PowerPC architecture). Module Type 100ns Pseudo Static RAM (PSRAM) Card.
While some of the products mentioned on this page may no longer be available, the information about these products remains available to those who may need it.
Be sure to mention the model number in the Comments field of the Ordering Form
when ordering upgrade modules from MacGurus.