Power Mac G5
The Power Mac G5 is Apple Computer's name for models of the Power Mac which utilize the PowerPC G5 processor. The current revision of the Power Mac G5 comes in three all-dual models with dual 1.8, dual 2.0 and dual 2.5 GHz PowerPC G5 processors. The G5 can communicate through its frontside bus at up to half its internal clock speed; a 2.5 GHz G5 thus has a 1.25 GHz FSB. Each processor in the G5 has two unidirectional 32-bit pathways: one leading to the processor and the other from the processor. These result in a total bandwidth of up to 20 GB/s. In addition, due to the 64-bit processor the G5 has a RAM capacity of eight gigabytes (a full four gigabytes above current theoretical limits on 32-bit processors). The processor at the heart of the PowerMac G5 has a "superscalar, superpiplined" execution core that can handle up to 216 in-flight instructions, and uses a 128-bit, 162-instruction SIMD unit.
Eleven-hundred Power Mac G5s form the processing nodes of Virginia Tech's original Mac OS X computer cluster supercomputer. The computer was soon dismantled and replaced with a new cluster made of an equal number of Apple's Xserve rack-mounted servers, which also use the G5 chip.
PowerPC G5 processor
The PowerPC G5 (called the PowerPC 970FX by its manufacturer, IBM) is based upon IBM's Power4 processor architecture. At the introduction of the Power Mac G5, Apple announced a partnership with IBM in which IBM would continue to produce PowerPC variants of their Power processors. According to IBM's Dr. John E. Kelly, "The goal of this partnership is for Apple and IBM to come together so that Apple customers get the best of both worlds, the tremendous creativity from the Apple corporation and the tremendous technology from the IBM corporation. IBM invested over 3 billion dollars in a new lab to produce these large, 300 millimeter wafers." (This lab is a completely automated facility located in East Fishkill, New York, and figures heavily in IBM's microelectronics strategy above and beyond the partnership with Apple.) The PowerPC G5 microprocessor has over 58 million transistors on it and it incorporates IBM's 90 nanometer fabrication process. That's 1/1000th the diameter of a human hair. The processor is manufactured with SOI technology, and IBM's additive-copper, dual-damascene wiring process allows for copper to be used in chip wiring. This processor is the first to impliment 64-bit technology.
Also, IBM is has already built the Power5, which is rumored to be the basis for the next generation of PowerPC processors. The Power5 has multiple improvements over the Power4 which includes IBM's version of Simultaneous Multi-threading, also known as hyper-threading, and advanced power management features. Due to the dual core nature of the Power 5 and it’s inclusion of Simultaneous Multi-threading, each CPU Core appear to be comprised of 4 CPUs. Other improvements include a dedicated single-tasking mode.
Product revision history
- 2003 June: Initial release at speeds of 1.6, 1.8, DP 2.0 GHz
- 2003 November: DP 1.8 replaces single processor 1.8GHz; a price reduction on 1.6 GHz
- 2004 June: 90 nm DP 1.8, DP 2.0 and liquid-cooled DP 2.5 GHz replace all previous models
A partial list of official firmware updates
- 15 December 2003: Version 5.1.4 (Apple Computer, Inc., 2003)
References
- Apple Computer, Inc. (2003). Power Mac G5 Firmware Update V 5.1.4: Information and Download. Retrieved December 19, 2003.
External links
- Apple: Power Mac
- Apple: PowerPC G5 Processor
- Ars Technica: Inside the PowerPC 970 Part 1 and Part 2 - very long and detailed.
- Ars Technica: A Brief Look at the PowerPC 970.