PowerPC 970
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In computing, the PowerPC 970, PowerPC 970FX, PowerPC 970GX, and PowerPC 970MP, are 64-bit processors in the PowerPC family from IBM. The PowerPC 970 was introduced in 2002.
The 970 family was made on the suggestion of Apple after Motorola failed to deliver any working 64-bit PowerPC. The project went under the codename GP-UL or Giga Processor Ultra Light, where Giga Processor was the codename for the POWER4. When Apple introduced the Power Mac G5 they stated that this was a five year collaborative effort, with multiple future generations, but it didn't last that long. Apple had to retract the promise to deliver a 3 GHz processor one year after its introduction and IBM could never get the power consumption down far enough for these processors to fit into a portable computer. Apple only used two variants of the processor.
Apple wasn't the only customer though. IBM offers its JS20/JS21 blade modules, Mercury Computing[1] the Momentum XSA-200 and Genesi[2] the TetraPower platform using the PowerPC 970MP. IBM is also licensing the PowerPC 970 core for use in custom applications.
A common misconception is that the PowerPC 970 was the core in Microsoft's Xenon processor in Xbox 360, but this is false.
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[edit] Design
The PowerPC 970 is built using a 130 nm manufacturing process, and the PowerPC 970FX and 970MP are built using a 90 nm fabrication process. They are based on the core from IBM's POWER4 processor. The 970 and 970FX feature over 58 million transistors, while the 970MP contains two cores, consisting of over 116 million transistors.
They feature IBM's VMX vector engine (a.k.a. AltiVec or Velocity Engine, also used in Freescale's PowerPC 7400). They are able to process both 32-bit and 64-bit PowerPC instructions natively.
[edit] Problems
- The PowerPC 970 ran at higher temperatures than older models, meaning it could not be fitted into Apple's PowerBook or iBook. As a result, Apple laptops continued to be fitted with the older G4 chip until the Apple-Intel transition.
- All PowerPC 970 models lack the instruction to do little/big endian swapping. This proved to be a problem for Microsoft Virtual PC, which relied on this feature in G3 and G4 processors to accelerate performance.
[edit] Processors
[edit] PowerPC 970
The PowerPC 970 was announced by IBM in October 2002. It was released in Apple Computer's Power Mac G5 in June 2003 (in keeping with its previous naming conventions, Apple termed the PowerPC 970 based products G5, for the fifth generation of PowerPC microprocessors). IBM released its first PowerPC 970 blade servers, the BladeCenter JS20, in November 2003.
The PowerPC 970 had 512 KB of full-speed L2 cache and clock speeds from 1.6 to 2.0 GHz. The front side bus ran at half the processor's clock speed.
[edit] PowerPC 970FX
The PowerPC 970FX used a 90 nm manufacturing process, which made it more power efficient.
Apple released their 970FX-powered machines throughout 2004: the Xserve G5 in January, the Power Mac G5 in June, and the iMac G5 in August. The Power Mac introduced a top clock speed of 2.5 GHz while liquid-cooled (eventually reaching as high as 2.7 GHz in April 2005). The iMac ran the front side bus at a third of the clock speed.
[edit] PowerPC 970MP
IBM released the PowerPC 970MP, code-named "Antares", in the 3rd quarter of 2005. The 970MP is a dual-core processor with clock speeds between 1.4 and 2.5 GHz. Each core has 1 MB of L2 cache, twice that of the 970FX. Like the 970FX, this chip was produced at the 90 nm process. When one of the cores is idle, it will enter a "doze" state and shut down. [3]
The PowerPC 970MP replaced the PowerPC 970FX in Apple's high-end Power Mac G5 computers, while the iMac G5 and the legacy PCI-X Power Mac G5 continued to use the PowerPC 970FX processor.
[edit] PowerPC 970GX
The single core version of PowerPC 970MP, the PowerPC 970GX, was released in October 2006. The PowerPC 970MP and 970GX share characteristics such as 1 MB L2 cache and speeds from 1.2 to 2.5 GHz and are made with the same 90 nm fabrication process. [4]
[edit] Northbridges
There are three dedicated northbridges for PowerPC 970-based computers, all made by IBM:
- CPC925—Called U3 or U3H (with ECC) by Apple. Manufactured on a 130 nm process. Dual 550 MHz bi-directional processor buses, 400 MHz DDR-controller, x8 AGP and 400 MHz 16-bit HyperTransport-tunnel. Capable of managing up to 2 processors (2x 970/970FX).
- CPC945—Called U4 by Apple. Manufactured on a 90 nm process. Dual 625 MHz bi-directional processor buses (1-4 processor cores), 533 MHz DDR2-controllers (up to 64 GB ECC RAM), x16 PCIe, and 800 MHz 16-bit HyperTransport-tunnel. Capable of handling up to 4 processors (2x 970MP).
- CPC965—Will be released in 2007. Is a single-processor bridge. Features a 533 MHz DDR2 controller (up to 8 GB ECC RAM), x8 PCIe, 4x Gbit Ethernet, USB2, Flash-interface, IPv4 TCP/UDP offloading, integrated PowerPC 405 processor for management and configuration. [5]
[edit] See also
- System X and MareNostrum—Supercomputers using the PowerPC 970.
