Apple PowerPC G5 manual For More Information, Three-component branch prediction logic

For More Information

For more information about the PowerPC G5 processor, visit www.apple.com/g5. For more information about the Power Mac G5, visit www.apple.com/powermac.

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PowerPC G5

Three-component branch prediction logic

•Speculative superscalar inner core organization

•Fast, selective flush of incorrect speculative instructions and results

•Prediction of up to two branches per cycle

•Support for up to 16 predicted branches in flight

•Prediction hints added to branch instructions

•Prediction support for branch direction and branch addresses

Physical specifications

•58 million transistors

•130-nanometer, silicon-on-insulator (SOI) process

•Die size: 118 square millimeters

Comparison of PowerPC G4 and PowerPC G5

	PowerPC G4	PowerPC G5
Architecture	32-bit	64-bit
Addressable memory	4 gigabytes	4 terabytes
Maximum clock speed	1.4GHz	2GHz
Frontside bus	Up to 167MHz shared	Up to 1GHz per processor
In-flight instructions	16	215
Floating-point units	One	Two
Integer units	One	Two
Load/Store units	One	Two
L1 data cache	32K	32K
L1 instruction cache	32K	64K
L2 cache	256K	512K
Branch prediction logic	Local	Local/Global/Selector
Process technology	180-nanometer	130-nanometer
Die size	106 square millimeters	118 square millimeters

1“World’s fastest” based on SPEC CPU2000 benchmark results and leading professional application performance tests against 3GHz Pentium 4–based Dell Dimension 8300 and dual 3.06GHz Xeon-based Dell Precision Workstation 650. SPEC CPU2000 benchmarks run with GCC 3.3 compiler and independently tested; professional applications tested by Apple, June 2003. 2Tests performed by Apple in June 2003 using preproduction Power Mac G5 units. The Power Mac systems ran a PowerPC G5–optimized version of Photoshop 7.0.1 including optimized AltiVecCore, ACE, and BIB Carbon Libraries; the Dell Dimension ran Photoshop 7.0.1. 3Based on SPEC CPU2000 benchmark results against 3GHz Pentium 4–based Dell Dimension 8300 and dual 3.06GHz Xeon-based Dell Precision Workstation 650m, performed by VeriTest, June 2003.

©2003 Apple Computer, Inc. All rights reserved. Apple, the Apple logo, Final Cut Pro, Mac, Mac OS, and Power Mac are trademarks of Apple Computer, Inc., registered in the U.S. and other countries. Velocity Engine is a trademark of Apple Computer, Inc. Adobe is a trademark or registered trademark of Adobe Systems Incorporated in the U.S. and/or other countries. PowerPC is a trademark of International Business Machines Corporation, used under license therefrom. SPEC is a registered trademark of the Standard Performance Evaluation Corporation (SPEC); see http://www.spec.org for more information. Other product and company names mentioned herein may be trademarks of their respective companies. Product specifications are subject to change without notice. This material is provided for informational purposes only;

Apple assumes no liability related to its use. July 2003 L29540B