This article describes the memory requirements for the Power Mac G4 (Digital Audio) computer.

The Power Mac G4 (Digital Audio) computer requires PC-133 memory, unlike previous Power Mac G4 models that used PC-100 memory. Apple System Profiler will tell you if the memory is PC-133 if the memory vendor identified it as such within the memory chip's circuitry.

Important: PC-100 DIMMs will not work in the Power Mac G4 (Digital Audio) computer.

The main logic board has three RAM expansion slots for SDRAM DIMMs. At least one of the RAM expansion slots contains a factory installed SDRAM DIMM. The SDRAM DIMMs can be installed one or more at a time.

The system supports linear memory organization; no performance gains are seen when two DIMMs of the same size are installed. Any supported size DIMM can be installed in any DIMM slot, and the combined memory of all of the DIMMs installed is configured as a contiguous array of memory. Mac OS 9 can work with a maximum memory size of 1.5 GB.

DIMM Specifications
The RAM expansion slots accept 168-pin SDRAM DIMMs that are 3.3 V, unbuffered, 8-byte, nonparity, and PC-133 compliant. The DIMMs can be implemented with either SDRAM or ESDRAM devices. ESDRAM devices provide higher performance for random read and write operations, but SDRAM devices are generally available in larger sizes.

Important: DIMMs with any of the following features do not work in the Power Mac G4 (Digital Audio) computer: registers or buffers, PLLs, ECC, parity, or EDO RAM.