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PowerPC G4 Microprocessor

The PowerPC G4 microprocessor used in the Power Mac G4 computer has many powerful features, including a pipelined system bus, called MaxBus, that is more efficient than the system bus on the PowerPC G3 microprocessors.

Two versions of the PowerPC G4 are used in different configurations of the Power Mac G4 computer. Both versions share the following features:

• 32-bit PowerPC implementation

• superscalar PowerPC core

• Velocity Engine (AltiVec technology): 128-bit-wide vector execution unit

• dual 32 KB instruction and data caches (level one)

• high bandwidth MaxBus

• fully symmetric multiprocessing capability

The G4 microprocessor in the configurations with 466 and 533-MHz clocks has

• support for up to 2 MB backside L2 cache

• on-chip L2 tag storage

The G4 microprocessor in the configurations with 667 and 733-MHz clocks has

• built-in 256 KB backside L2 cache

• support for up to 2 MB backside L3 cache

• on-chip L3 tag storage

To find more information, see the reference at PowerPC G4 Microprocessor.