The End of the PowerPC Era

The Macintosh was introduced in 1984 using the same 68000 processor that powered Apple’s $10,000 Lisa, introduced a year earlier. Over the years, Apple moved to faster and more efficient chips as they became available. At the same time, Apple was paying attention to a new design theory for microprocessors, RISC (Reduced Instruction Set Computing). Motorola and IBM had both been working on RISC CPUs, and Apple got the two to join together with Apple to develop a new RISC architecture, PowerPC, based on IBM’s POWER processor.

The first PowerPC (PPC) Macs shipped in 1994, and Apple stuck with PPC processors through 2005. That was the year Apple announced it would be switching from PPC to Intel x86 CPUs, the same family of processors used in Windows PCs. The rest, as they say, is history, and after the Intel transition, Mac sales reached their highest levels ever – and the end is not yet in sight.

The last new PowerPC Macs were introduced on October 19, 2005. The Power Mac G5 Dual used a 2.0 GHz or 2.3 GHz dual-core G5 CPU, and the Power Mac G5 Quad used two 2.5 GHz dual-core CPUs. These were the only PowerPC Macs designed around dual-core chips. (Last week, Freescale announced a 12-core PowerPC chip, which has more cores than any shipping Intel CPU.) Today we look at what was and what could have been, such as PowerBooks designed around dual-core G4 CPUs.

Brian Gray (Fruitful Editing): In the fall of 2005, I bought my first refurbished Mac, a first generation iMac G5. The Intel rumors were strong in the fall of 2005, so I knew there would be a huge shift in the Mac architecture in the near future. I had faith that Apple would keep me supported for quite a while. Fast forward to 2009. I no longer held faith that Apple was going to continue PPC support, and a few months later the introduction of Intel-only OS X 10.6 Snow Leopard reinforced that.

I think that Apple made the correct decision to switch to Intel – and for two very important reasons. The first is compatibility with Windows: There is no doubt in my mind that this was a major feature for the users who were “on-the-fence” about Apple hardware not being able to run Windows natively. With the introduction of Boot Camp, the argument became moot. You want Windows? Install it. End of story.

The second is power consumption. The PPC G5 processor has been referred to as a “thermal nightmare” in notebooks. That didn’t stop Microsoft from including a 3.2 GHz PPC in its Xbox 360 console in 2005. Judging from the number of Xbox 360 consoles that have had the “red ring of death” from overheating, I’d guess that PPC would have been a disastrous choice to include in future Apple notebooks.

Dan Knight (Mac Musings): One of the great ironies is that at the same time that Apple was abandoning PowerPC, Microsoft was embracing it.Ê Microsoft software had been available for the Apple II and Mac for years, and in 1995 Microsoft even released a PowerPC version of Windows NT 3.51, so Microsoft was no stranger to PowerPC, even though the bulk of its business was built around Intel x86 hardware.

Apple’s attempt to launch a gaming platform, known as Pippin, was a failure. The console was more or less a slower Performa 6200 with less system memory, no hard drive, and no floppy drive. It ran a modified version of the Mac OS, and it loaded the operating system and games via its 4x CD-ROM drive. The only commercial version of the platform, the Bandai Atmark, launched in March 1995 and was discontinued in 1997 after selling less than 50,000 units.

Microsoft decided to get in the gaming console business and launched its Xbox in November 2001. It ran a custom version of Windows rooted in NT and XP, used a custom 733 MHz Pentium III processor, and included a built-in hard drive. Games shipped on CD or DVD, and Microsoft sold over 24 million units, reaching second place in the North America console market in 2002.

Four years later, in November 2005, Microsoft shipped the Xbox 360, which curiously was built around a custom triple-core PowerPC processor – the same PowerPC architecture Apple had announced it was abandoning for Intel x86 just months earier. At the same time, Sony was preparing its PlayStation 3, which would also be built with a custom PowerPC Cell CPU. (The PlayStation 2 had uses a custom “Emotion Engine” CPU.)

Nintendo’s had switched to PowerPC with the Game Cube in 2001, and its Wii (released in November 2006) also has a PowerPC core, so by the end of 2006, the three major gaming consoles had all moved to custom IBM PowerPC processors. This was the same year that Apple moved its entire Macintosh line from PowerPC to Intel x86. Ironic.

In terms of what could have been, Motorola announced a dual-core e600 G4 CPU, the MPC8641D, in late 2004. With clock speeds up to 1.5 GHz, it’s a shame Apple never released a dual-core G4 PowerBook or Mac mini. The primary reason was probably that the Power Mac and iMac had already moved to G5 (a.k.a. PowerPC 970) CPUs, and it may have felt like a step backwards. Problem was, the G5 was energy hungry and ran too hot to be used in a laptop computer, so PowerBook users were stuck at 1.67 GHz G4 performance while the consumer iMac G5 achieved clock speeds as high as 2.1 GHz. A dual-core 1.5 GHz G4 would have been even more powerful than the 2.1 GHz iMac G5 (that iMac scores 1179 on Geekbench, the dual 1.42 GHz Power Mac G4 has a score of 1234, and we can estimate that a dual-core 1.5 GHz G4 would have been in the 1300+ range).

The last PowerPC Macs were quite a bit more powerful than that. The 2.0 GHz dual-core G5 achieved a Geekbench score of 1967, 7.7% better than the previous dual-CPU 2.0 GHz Power Mac G5. The dual-core 2.3 GHz model hit 2084, a 5.6% improvement over the previous dual-CPU model running at the same clock speed. And the four-core 2.5 GHz Power Mac G4 Quad, with two dual-core CPUs, rates 3318, which is as much power as the 2.4 GHz Core 2 Duo Early 2008 iMac and over 80% as powerful as the 2.0 GHz quad-core 2006 Mac Pro.

Although one of the reasons Apple left PowerPC for Intel was IBM’s inability to deliver a promised 3.0 GHz G5 CPU on schedule, today IBM is building 4-, 6-,and 8-core POWER7 CPU in speeds ranging from 2.4 GHz to 4.25 GHz. And while the Intel world is excited about HyperThreading allowing two processes per core, POWER7 supports up to four processes per core.

IBM builds its entire computing business around its POWER architecture, which formed the basis for PowerPC, and the three leading gaming consoles are also firmly rooted in IBM POWER architecture, while the entire Windows world (not counting mobile/phone editions) is wed to x86 – as is Apple since 2006.

It’s interesting to speculate about what might have been, but the reality is that a lot of use are still being very productive with our G3, G4, and G5 Macs. Apple may have phased out PowerPC five years ago, but there’s a lot of life in this old hardware.

Short link:

searchword: endofppc