Malaysian magazine The Star Online has published an interesting piece on the PowerPC. The piece is an abridged history of PowerPC development that specifically looks at how and why G4 development was stalled, and how the G5 came to market. The author also points out the irony that it took the company that was once perceived as Appleis greatest enemy to get the company back in the race for speed. From the article:
The PowerPC architecture started as a joint venture between Apple, IBM and Motorola. In the early stages of its lifecycle, the platform was neck-to-neck with Intel x86 processors in the MHz race.
Unfortunately, things started to go awry shortly before the introduction of the G4, which was the first PowerPC to include the performance-boosting Altivec SIMD (Single Instruction Multiple Data) unit.
Altivec is similar to Intelis MMX, SSE and SSE2 extensions but is widely regarded as one of the best SIMD units ever designed. In fact, itis credited as the main reason why G4s are able to keep up with Pentium 4s, which have much higher clock speeds.
IBM initially rejected Altivec and, after a series of events, Motorola became the sole developer of the G4 while IBM concentrated on its predecessor, the G3 (the G3 is very similar to the G4 in design but lacks the Altivec unit. It was used in the original iMac and, until recently, the iBook).
Thereis not a lot of new information in the full article, but those interested in learning more about PowerPC history will find it to be an interesting read.