The Power Mac G5 is a series of personal computers designed, manufactured, and sold by Apple Computer, Inc. from 2003 to 2006 as part of the Power Mac series. When introduced, it was the most powerful computer in Apple's Macintosh lineup, and was marketed by the company as the world's first 64-bit desktop computer. It was also the first desktop computer from Apple to use an anodized aluminum alloy enclosure, and one of only three computers in Apple's lineup to utilize the PowerPC 970 CPU, the others being the iMac G5 and the Xserve G5.
Three generations of Power Mac G5 were released before it was discontinued as part of the Mac transition to Intel processors, making way for its replacement, the Mac Pro. The Mac Pro retained a variation of the G5's enclosure design for seven more years, making it among the longest-lived designs in Apple's history.
Introduction Officially launched as part of Steve Jobs' keynote presentation at the Worldwide Developers Conference in June 2003, the Power Mac G5 was introduced with three models, sharing the same physical case, but differing in features and performance. Although somewhat larger than the G4 tower it replaced, the necessity for a complex cooling system meant that the G5 tower had room inside for only one optical drive and two hard drives. The lack of drive expansion caused enough problems for some users that 3rd party manufacturers introduced a number hard drive brackets that mounts in front of the front CPU fans providing room for three additional drives. They typically use a splitter cable from the optical drive for power and require the end user to provide their own storage controller card with internal ports to interface with the Power Mac G5.G5 JiveMaxConnect Lite CPU Bay Disk Drive Mounting Assembly PolyAcetal for G5 Power Macs (PCI-X)G5 Drive BracketSwiftData 200G5Jam
Steve Jobs stated during his keynote presentation that the Power Mac G5 would reach 3 GHz "within 12 months." This would never come to pass; after three years, the G5 only reached 2.7 GHz before it was replaced by the Intel Xeon-based Mac Pro, which debuted with processors running at speeds of up to 3 GHz.
During the presentation, Apple also showed Virginia Tech's Mac OS X computer cluster supercomputer (a.k.a. supercluster) known as System X, consisting of 1,100 Power Mac G5 towers operating as processing nodes. The supercomputer managed to become one of the top five supercomputers that year. The computer was soon dismantled and replaced with a new cluster made of an equal number of Xserve G5 rack-mounted servers, which also used the G5 chip running at 2.3 GHz.
PowerPC G5 and the IBM partnership
The PowerPC G5 (called the PowerPC 970 by its manufacturer, IBM) is based upon IBM's 64-bit POWER4 microprocessor. At the Power Mac G5's introduction, 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 US$3 billion in a new lab to produce these large, 300 mm wafers." This completely automated facility in East Fishkill, New York figured heavily in IBM's larger microelectronics strategy.
The original PowerPC 970 had 50 million transistors and was manufactured using IBM CMOS 9S at 130 nm fabrication process. CMOS 9S is the combination of SOI, low-k dielectric insulation, and copper interconnect technology, which were invented at IBM research in the mid-1990s. Subsequent revisions of the "G5" processor have included IBM's PowerPC 970FX (same basic design on a 90 nm process), and the PowerPC 970MP (essentially two 970FX cores on one die). Apple refers to the dual-core PowerPC 970MP processors as either the "G5 Dual" (for single-socket, dual-core configurations), or Power Mac G5 Quad (for dual-socket, four-core configurations).
Architecture
The Power Mac G5 line in 2006 consisted of three, dual-core PowerPC G5 configurations, which can communicate through its HyperTransport at half its internal clock speed. Each processor in the Power Mac 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. The processor at the heart of the Power Mac G5 has a "superscalar, superpipelined" execution core that can handle up to 216 in-flight instructions, and uses a 128-bit, 162-instruction SIMD unit (AltiVec).
All modern 32-bit x86 processors since the Pentium Pro have the Physical Address Extension (PAE) feature, which permits them to use a 36-bit physical memory address to address a maximum of 236 bytes (64 gigabytes) of physical memory, while the PowerPC 970 processor is capable of addressing 242 bytes (4 terabytes) of physical memory and 264 bytes (16 exabytes) of virtual memory. Due to its 64-bit processor (and 42-bit MMU), the final revision of the Power Mac G5 can hold 16 GB of Dual-Channel DDR2 PC4200 RAM using eight memory slots, with support for ECC memory.
Product revision history
June 2003: Initial release at speeds of Single 1.6, Single 1.8, Dual 2.0 GHz. November 2003: Dual 1.8 replaces Single 1.8 GHz; price reduction on Single 1.6 GHz. June 2004: 90 nm Dual 1.8, Dual 2.0 and Dual 2.5 GHz replace all previous models. The 2.5 GHz model is notable as the first major PC with liquid cooling included as stock. October 2004: A new Single 1.8 reintroduced, with a slower, 600 MHz HyperTransport, PCI bus, based upon the iMac G5's architecture (U3lite and Shasta chips). Apple's official name for this machine is "Power Mac G5 (Late 2004)". April 2005: CPU speed increased: Dual 2.5 GHz → Dual 2.7 GHz (PCI-X, more reliable liquid cooling), Dual 2.0 GHz → Dual 2.3 GHz (PCI-X), Dual 1.8 GHz → Dual 2.0 GHz (PCI). Newly introduced features were the 16x dual-layer SuperDrives across the line and increased storage, up to 800 GB for the higher-end models. The 1.8 GHz Single was not modified. June–July 2005: The Single 1.8 model was discontinued in the United States and Europe. October 2005: Shift to dual-core processors: Dual 2.0 GHz → DC 2.0 GHz, Dual 2.3 GHz → DC 2.3 GHz, Dual 2.7 GHz → Dual DC 2.5 GHz (termed a Quad Power Mac G5, with four CPU execution cores), all with DDR2 memory, and PCI Express expansion in place of PCI-X. The older PCI-X, Dual 2.7 GHz model remained available for a while, but the slower speed single-core models were discontinued immediately. August 2006: The Power Mac is replaced by its Intel successor, the Mac Pro.
Technical specifications
Model Mid 2003 Late 2004 Early 2005 Late 2005 Codename "Omega, Q37" "Niagara, Q77, Q78" colspan=3 "Cypher" Timetable Released June 23, 2003 November 18, 2003 June 9, 2004 October 19, 2004 April 27, 2005 October 19, 2005 Discontinued June 9, 2004 November 18, 2003 June 9, 2004 April 27, 2005 June 13, 2005 October 19, 2005 August 7, 2006 Model Model number A1047 A1093 A1047 A1117 Model identifier PowerMac7,2 PowerMac7,3 PowerMac9,1 PowerMac7,3 PowerMac11,2 Order number M9020 M9031 M9032 M9393 M9494 M9454 M9455 M9457 M9555 M9747 M9748 M9749 M9590 M9591 M9592 Performance Processor Single PowerPC 970 (G5) Dual PowerPC 970 (G5) Dual PowerPC 970FX (G5) Single PowerPC 970FX (G5) Dual PowerPC 970FX (G5) Single Dual-core PowerPC 970MP (G5) Two Dual-core ("Quad-core") PowerPC 970MP (G5) Clock speed 1.6 GHz 1.8 GHz 2.0 GHz 1.8 GHz 2.0 GHz 2.5 GHz 1.8 GHz 2.0 GHz 2.3 GHz 2.7 GHz 2.0 GHz 2.3 GHz 2.5 GHz Cache 64 KB (instruction), 32 KB (data) L1, 512 KB L2 64 KB (instruction), 32 KB (data) L1, 1.0 MB L2 per core HyperTransport 800, 900, Dual 900 MHz, or Dual 1 GHz (2:1) Dual 900 MHz, Dual 1, or Dual 1.25 GHz (2:1) 600 MHz (3:1) Dual 1 GHz (2:1) Dual 1.15 GHz (2:1) Dual 1.35 GHz (2:1) Dual 1 GHz (2:1) Dual 1.15 GHz (2:1) Dual 1.25 GHz (2:1) Memory Amount 256 MB 512 MB 256 MB 512 MB 256 MB 512 MB Type PC-2700 DDR SDRAM PC-3200 DDR SDRAM PC-2700 DDR SDRAM PC-3200 DDR SDRAM PC2-4200 DDR2 SDRAM Maximum Graphics Type NVIDIA GeForceFX 5200 Ultra, GeForce 6800 Ultra DDL, ATI Radeon 9600 Pro, or Radeon 9800 Pro NVIDIA GeForceFX 5200 Ultra ATI Radeon 9600 XT NVIDIA GeForceFX 5200 Ultra ATI Radeon 9600 ATI Radeon 9650 NVIDIA GeForce 6600 LE NVIDIA GeForce 6600 VRAM 64, 128, or 256 MB DDR RAM 64 MB DDR RAM 128 MB DDR RAM 64 MB DDR RAM 128 MB DDR RAM 256 MB DDR RAM 128 MB GDDR RAM 256 MB GDDR RAM Storage Hard drive 80 GB Serial ATA 7200-rpm 160 GB Serial ATA 7200-rpm 80 GB Serial ATA 7200-rpm 160 GB Serial ATA 7200-rpm 80 GB Serial ATA 7200-rpm 160 GB Serial ATA 7200-rpm 250 GB Serial ATA 7200-rpm 160 GB Serial ATA 7200-rpm 250 GB Serial ATA 7200-rpm Optical drive 4x SuperDrive 4x/8x/16x/8x/32x DVD-R/CD-RW 8x SuperDrive 8x/10x/24x/10x/32x DVD-R/CD-RW 16x SuperDrive DVD+R DL/DVD±RW/CD-RW Peripherals Connectivity Gigabit Ethernet56k V.92 modem Gigabit Ethernet 2x Gigabit Ethernet Expansion slots 3x 33 MHz 64-bit PCI1x 8x AGP Pro (1.6 GHz) 3x 33 MHz 64-bit PCI 1x 8x AGP Pro (1.8 GHz) 3x 33 MHz 64-bit PCI 1x 8x AGP Pro 3x 33 MHz 64-bit PCI 1x 8x AGP Pro (2.0 GHz) 2x PCI Express x41x PCI Express x81x PCI Express x16 2x 100 MHz 64-bit PCI-X1x 133 MHz 64-bit PCI-X1x 8x AGP Pro (1.8 GHz single+) 2x 100 MHz 64-bit PCI-X1x 133 MHz 64-bit PCI-X1x 8x AGP Pro (2.0 GHz+) 2x 100 MHz 64-bit PCI-X1x 133 MHz 64-bit PCI-X1x 8x AGP Pro (2.3 GHz) Peripherals 3x USB 2.02x FireWire 4001x FireWire 800Built-in mono speaker1x Audio-in mini-jack2x Audio-out mini-jack1x Optical S/PDIF (Toslink) input1x Optical S/PDIF (Toslink) output 4x USB 2.02x FireWire 4001x FireWire 800Built-in mono speaker1x Audio-in mini-jack2x Audio-out mini-jack1x Optical S/PDIF (Toslink) input1x Optical S/PDIF (Toslink) outputOperating SystemOriginalMac OS X 10.2.7 "Jaguar"Mac OS X 10.3.4 "Panther"Mac OS X 10.3.5 "Panther"Mac OS X 10.4 "Tiger"Mac OS X 10.4.2 "Tiger"Maximum Mac OS X 10.5.8 "Leopard" Weight
Defects
Early versions of dual processor G5 computers have noise problems. The first one is ground loop-based interference, which sometimes causes noise leaks into the analog audio outputs. This bug was fixed in Rev. B G5.
The second noise problem came from the 'chirping' sound, which can be triggered by fluctuations in power draw. For example, using Exposé causes a brief chirp. A widely circulated work-around is to disable the CPUs' "nap" feature using Apple's CHUD Tools, but this was not recommended by Apple. This noise problem was not fixed until the dual core generation of G5s was produced, however it did not affect the "Late 2004" model (at least there have never been any reports). The power draw fluctuation was later attributed to the lack of power management features in the single-core processors. Apple eventually posted the chirping bug information on its support site.
Although the noise problems did not prevent the affected computers from working, they were problematic for audio professionals and enthusiasts, especially for the liquid-cooled models, which had been expressly designed as mechanically quiet for discerning listeners.
A common problem among single processor G5s was the cyclic expansion and contraction of a metal plate soldered to the Logic Board connecting all eight of the RAM slots. Eventually, this can cause the computer to no longer detect the RAM, and refuse to boot. Fixes for this include having the plate re-soldered, or exposing the other side of the Logic Board to heat from a heat gun. The latter option is far easier, since it requires neither soldering nor the removal of the Logic Board from the computer.