This article provices the memory specifications and upgrade options for the Power Mac G4 (AGP Graphics). Article 58425: " Power Mac G4 (PCI Graphics): Upgrading Memory " has information on upgrading the RAM in that Power Mac G4.

The Power Mac G4 logic board provides four PC-100 DIMM slots.

Compatible DRAM DIMMs must meet all the following specifications:

• PC-100 Synchronous DRAM (SDRAM)
• 3.3 volt
• 64-bit wide, 168-pin module
• Maximum of 16 memory devices on the DIMM
• Unbuffered; do not use registered or buffered Synchronous DRAM (SDRAM)
• Maximum height of 2.0 inches.

The computer comes from Apple with one DIMM slot populated with a 128 MB DIMM. Additional DIMMs can be installed in any order, in any size. There is no performance benefit to matching DIMM sizes or installing them in pairs.