All PowerMac G3 Models take the same kind of RAM (PC100/133) regardless of the processor speed.

Pay attention to the G4 model that you have. Apple changed RAM types around for the different models. Some models take the same PC100/133 RAM, while others take PC133 Only, or DDR RAM.

The PowerMac G5 for the most part all takes the same PC3200 DDR RAM. Remember that ALL PowerMac G5 models require you to install RAM in matched pairs. This means that if you want to upgrade your PowerMac G5 to another 1GB, you'll need to install (2) 512MB DDR models. You cannot just install a 512MB DDR DIMM. The PowerMac will not recognize it. Also note that the very last PowerMac G5 model (late 2005) requires DDR2 RAM, not DDR RAM.

If you're looking for MacPro RAM, please see the MacPro section.

PowerMac

G3 Processor


300/350/400/450 MHz G3 (Blue & White)
PC100 DIMM
Max RAM 1 GB

G4 Processor


350/400/450/500 MHz G4 (Graphite)
PC100 DIMM
Max RAM 2GB (1.5 GB OS 9)

2x400/2x450/2x500 MHz G4 (Gigabit Ethernet)
PC100 DIMM
Max RAM 2GB (1.5 GB OS 9)

2x466/2x533/2x667/2x733 MHz G4 (Digital Audio)
PC133 DIMM
Max RAM 2GB (1.5 GB OS 9)


733/867/2x800 MHz G4 (Quicksilver)
PC133 DIMM
Max RAM 2GB (1.5 GB OS 9)

800/933 MHz/2x1 GHz G4 (Quicksilver 2002)
PC133 DIMM
Max RAM 2GB (1.5 GB OS 9)




2x867 MHz/2x1.0/2x1.25 GHz G4 (Mirror Doors)
PC2100 DDR DIMM
Max RAM 2GB (1.5 GB OS 9)

2x1.0/2x1.25/2x1.42 GHz G4 (Mirror Doors FW800)
PC2100 DDR DIMM
Max RAM 2GB (1.5 GB OS 9)

1.25/2x1.25 GHz G4 (Mirror Doors 2003)
PC2700 DDR DIMM
Max RAM 2GB (1.5 GB OS 9)


450/500 MHz G4 (G4 Cube)
PC100/133 DIMM
Max RAM 1.5GB


G5 Processor



1.6 GHz G5
PC2700 DDR DIMM
Max RAM 4GB

1.8/2x1.8/2x2.0
PC3200 DDR DIMM
Max RAM 4GB

2x1.8/2x2.0/2x2.5 GHz (June 2004)
PC3200 DDR DIMM
Max RAM 4GB (1.8 GHz only) 8GB (2.0/2.5 GHz)

2x2.0/2x2.3/2x2.7 GHz (Early 2005)
PC3200 DDR DIMM
Max RAM 4GB (2 GHz only) 8GB (2.3/2.7 GHz)

2x2.0/2x2.3/2x2.7 GHz (Late 2005)
PC2-4200 DDR2 DIMM
Max RAM 8GB