From Wikipedia, the free encyclopedia.
In the product line of the computer manufacturer Apple, the Power Macintosh G5 are models of the Power Macintosh, announced in June 2003. They were dubbed Power Macintosh G5, because they incorporated PowerPC 970 microprocessors (termed G5 by Apple), running at speeds of 1.6, 1.8, and in a dual-chip version, 2.0 GHz. (A dual 1.8 GHz model has since been introduced.) The G5 can communicate through its frontside bus at up to half its internal clock speed; a 2 GHz G5 thus has a 1 GHz frontside bus, and due to the 64-bit processor the G5 has a RAM ceiling of eight gigabytes (a full four gigabytes above current theoretical limits on 32-bit processors). The G5 has a "superscalar, superpiplined" execution core that can handle up to 216 in-flight instructions. The technology behind the IBM PowerPC 970 (based on IBM's POWER4 design paired with a 128-bit, 162-instruction SIMD unit for Apple's use) and that of the Power Macintosh G5 is cutting-edge for a desktop system as of its introduction.
In June 2003, Steve Jobs, Apple Computer CEO, announced that chips running at speeds of 3.0 GHz would be available "within a year."
The PowerPC 970 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 fab to produce these large, 300 millimeter wafers. (This fab 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.) This G5 microprocessor has over 50 million transistors on it and it incorporates IBM's leading edge 130 nanometer technology. That's 1/800th the diameter of a human hair, but this is only the beginning. We have already built the prototypes for next-generation PowerPC microprocessors." This is apparently a reference to IBM's work on the Power5 (the successor to the Power4), and the PowerPC equivalent thereof.
The Power5 has multiple improvements over the Power4 which includes IBM's version of hyper-threading and a multi-core layout. This in effect allows 4 threads to be run simultaneously. Other improvements include a dedicated single-tasking mode and better power management.
Eleven-hundred Power Macintosh G5s form the processing nodes of the Virginia Tech Mac OS X computer cluster supercomputer.
Product revision history
A partial list of official firmware updates
References
External links
