Barrapunto

¿Quieres enlaces? pues toma enlace [wikipedia.org].

PowerPC is a RISC microprocessor architecture created by the 1991 Apple-IBM-Motorola alliance, known as AIM. Originally intended for personal computers, PowerPC CPUs have since become popular embedded and high-performance processors as well. PowerPC was the cornerstone of AIM's PReP and Common Hardware Reference Platform initiatives in the 1990s, but the architecture found the most success in the personal computer market in Apple's Power Macintosh line from 1994-2005. PowerPC is largely based on IBM's earlier POWER architecture, and retains a high level of compatibility with it; the architectures have remained close enough that the same programs and operating systems will run on both if some care is taken in preparation.

Y ademas, añade y quita cosas sobre POWER

The PowerPC is designed along RISC principles, and allows for a superscalar implementation. Versions of the design exist in both 32-bit and 64-bit implementations. Starting with the basic POWER specification, the PowerPC added:

• Support for operation as in both big-endian and little-endian modes; the PowerPC can switch from one mode to the other at run-time (see below). This feature is not supported in the PowerPC G5. (This was the reason why Virtual PC took so long to be made functional on G5-based Macintoshes.)
• Single-precision forms of some floating point instructions, in addition to double-precision forms
• Additional floating point instructions at the behest of Apple
• A complete 64-bit specification, which is backward compatible with the 32-bit mode
• Removal of some of the more esoteric POWER instructions, some of which could be emulated by the operating system if necessary.

Y como puedes ver [wikipedia.org], PowerPC 970 o G5 es basado en POWER4

970 (PowerPC G5) (2003) A 64-bit implementation derived from the IBM POWER4 enhanced with VMX (AltiVec compatible SIMD extensions) operating at speeds of 1.4 GHz, 1.6 GHz, 1.8 GHz, 1.9 GHz, 2.0 GHz, 2.1 GHz, 2.3 GHz, 2.5 GHz and 2.7 GHz

A lo que iba, que PowerPC está basado en POWER, pero no puedes decir que los Mac usan POWER4 o POWER5, porque no es cierto, son procesadores diferentes de un tronco común, que es la arquitectura POWER [wikipedia.org]