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PowerPC G3 Microprocessor

The processor in the Power Macintosh G3 computer is a PowerPC 750 microprocessor running at 300 MHz, 350 MHz, or 400 MHz. Apple refers to these processors as PowerPC G3 microprocessors (G3 stands for "generation three").

The principal features of the PowerPC G3 microprocessor include

• full RISC processing architecture
• parallel processing units: load-store unit, two integer units, one complex integer unit, and one floating-point unit
• a branch manager that can usually implement branches by reloading the incoming instruction queue without using any processing time
• integrated L2 cache controller and Tag RAMs for high-performance memory access
• an internal memory management unit (MMU)
• 64 KB of on-chip cache memory (32 KB each for data and instructions)

For complete technical details, see the PowerPC Web pages at <http://www.mot.com/SPS/PowerPC/index.html> and <http://www.chips.ibm.com/products/ppc/overview/>.

The PowerPC G3 is located on a plug-in microprocessor card that includes the L2 cache.