(1) A series of Macintosh desktop machines from Apple that use the 64-bit IBM PowerPC 970 CPU, a single-chip version of IBM's POWER4 family. Introduced in 2003, the G5 has a 1 GHz frontside bus and can access up to 8GB of memory. G5 models support the PCI-X bus and Serial ATA (SATA) interface for hard disks. The Power Mac G5 was the last Macintosh to use the PowerPC chips (see Mac Pro). See G4, Apple and POWER.