Apple PowerPC G5 Technical Specifications, Bit PowerPC processor architecture, Frontside bus

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PowerPC G5

Technical Specifications

64-bit PowerPC processor architecture

•Virtual address range: 64 bits, or 18 exabytes

•Physical address range: 42 bits, or 4 terabytes

•Full 64-bit data paths and registers

•Native support for 32-bit application code

•64K L1 instruction cache; 32K L1 data cache

•512K internal L2 cache

•Dedicated data flow for dividing one instruction into two internal operations

•Microcoded instructions for up to four internal operations

•Support for up to eight outstanding L1 cache line misses

•Hardware-initiated instruction prefetching from L2 cache

•Hardware- or software-initiated data stream prefetching; support for up to eight active streams

•Maximum core frequency: 2GHz

Frontside bus

•Throughput: up to 8 GBps per processor

•Frequency: 1GHz DDR

•Width: 64-bit (32-bit in, 32-bit out) bidirectional

Wide execution core

•Support for up to 215 in-flight instructions

•In-order dispatch of up to five operations into distributed issue queue structure

•Simultaneous issue of up to 10 out-of-order operations:

–One Velocity Engine permute operation

–One Velocity Engine arithmetic logic operation

–Two floating-point operations

–Two fixed-point register-to-register operations

–Two load or store operations

–One condition register operation

–One branch operation

•Out-of-order and speculative issue of load operations

•Dual-pipeline 128-bit Velocity Engine for single-instruction, multiple-data (SIMD) processing

•Two independent floating-point units for double-precision calculations