PowerPC G3 a Huge Step Forward in Its Day

Sometimes, as with the last round of MacBook Pro updates, processor performance takes a small step forward. In fact, that's the case more often than not, with relatively insignificant 5-10% speed bumps being the norm.

But every now and then there's a breakthrough that doubles performance. For Mac users, those breakthroughs were the Macintosh II, which doubled processor speed while also adopting a more powerful chip design in 1987, the Quadra 700 and 900, which introduced the far more efficient 68040 CPU in 1991, the PowerBook G3 and Power Mac G3, which offered nearly twice the processing power per MHz in November 1997, and the Intel Core i family, which Apple has moved to over the past year.

Today, 14 years after the first G3 Macs were introduced, our staff looks at those performance leaps from yesterday and today.

Charles Moore (several columns): Having been on the Mac for going on 20 years now, I've experienced first-hand many of the platform's performance advance transitions. My first Mac was a Mac Plus with an 8 MHz 68000 processor, so there was lots of room for improvement, although to be fair, at least when running System 6, the old Plus was pretty lively.

My next step up was an LC 520, the all-in-one variant of the modular LC III, with a 25 MHz 68030 CPU. In practical terms, the speed increase from the Plus wasn't really all that dramatic, the biggest difference was in expansiveness and versatility rather than speed. The LC 520, running System 7.1, was a much more comprehensively capable machine than the Plus, and of course the 14" 640 x 480 resolution Sony Trinitron display was the major difference from the Plus' 9" 512 x 342 screen. Color was nice, but I found myself missing the ultra sharp one-bit display in the Plus for things like text editing and Finder navigation. Not so much for the Internet.

As an aside, I did install System 7.0 on the Plus for more tractable Internet access, but it was exceedingly sluggish - one-bit 9" displays were woefully inadequate for Web surfing, and I kept System 6.0.8 installed on another partition (this was on a 20 MB hard drive!) for performance purposes when the Internet wasn't an issue - this being long before Cloud computing.

I never had either a 68020 or a 68040 Motorola Mac, although one of my offspring did have PowerBook 520 with a 68LC040 chip.

My next step up from the LC 520 was a PowerBook 5300, a much-maligned machine that I nevertheless developed an affection for. Irreally liked the form factor, and it was a pretty dependable machine once I upgraded to System 7.5.3 and then System 7.5.5 from the original (and genuinely execrable) System 7.5.2. Some of the famous issues with the PowerBook 5300 were legitimate shortcomings, although the famous spontaneous battery combustion was way overblown, with the self-immolating early example lithium ion batteries that had been planned for the 5300 quickly replaced. It wasn't the most robust Apple laptop, but treated kindly that one remained in service for seven years - four as my main workhorse and then three as my youngest daughter's high school computer. In general, it was a pretty good experience. It still worked the last time I booted it up, which was several years ago. Again, the overall performance profile wasn't that much improved from the predecessor machine, and the 68K PowerBook 500 actually was faster at some tasks, but where the 100 MHz PowerPC 603e excelled was in anything that required floating-point unit computation. The PowerPC chip incorporated an FPU, while with the 68K machines was an add-on that many models didn't have on board (e.g., the LC520 and PowerBook 520).

Probably the most dramatic surge in processing power I've experienced with a system upgrade was in making the jump from the PowerBook 5300 to a 233 MHz WallStreet PowerBook G3 in early 1999. The G3 Series PowerBook was a quantum improvement in speed over the puny 603e chip in the 5300. By contrast, moving to a 500 MHz G3 in the PowerBook 2000 Pismo that succeeded the WallStreet as my number one axe was much less of a performance boost, notwithstanding more than doubling of the CPU clock speed. Nor was the 700 MHz G3 iBook that succeeded the Pismo as my front line workhorse machine noticeably much faster than the 500 MHz G3 PowerBook - andÊ once I installed a 550 MHz G4 upgrade in the Pismo, it leapfrogged back over the iBook as my fastest computer at the time.

The 1.33 GHz 17" PowerBook G4 that became my next system upgrade was far and away the fastest PowerPC machine that I ever owned (still in service as my wife's computer) and a major advance over the iBook. Having 1.5 GB of RAM helped, of course.

My current Mac, a 2.0 GHz Core 2 Duo Aluminum Unibody MacBook of the late 2008 design is again hands down the fastest Mac I've ever owned so far, which means that I have lots of room to experience improved performance. However, I find that the relatively low powered Core 2 Duo chip (and 4 GB of RAM) still provides what I would call sparkling performance.

I'm looking forward to another major speed boost when I eventually move on to a Core "i" powered MacBook of some sort, but for now, I really have nothing to complain about with the nearly 3-year-old MacBook. That said, the fastest Apple machine I own these days is my iPad 2. I just wish it was more versatile in other ways!

Allison Payne (The Budget Mac): Considering the fact that Moore's Law and strained flash storage supplies mean computing speed should be leveling off, it's impressive to see how manufacturers are still managing to find ways to visibly boost performance. The big leaps forward that come to mind from my personal experience are USB 1.1 to USB-2.0, the difference between surfing the Web from the original iPod touch and the 4G touch, and the speed boost one sees with SSDs over traditional hard drives. The difference is definitely noticeable at first, but it really hits home when you use a Mac or iPod with the older standards after getting used to the speed increase.

Dan Knight (Mac Musings): I first used a Mac in 1986, so I've experienced most of these improvements in processor efficiency. In 1987, the 16 MHz Mac II added color, a larger display, and expansion slots while offering almost three times the processing power of the Mac Plus. The 33 MHz 68040 CPU in the Quadra 700 and 900 was another big step forward, roughly twice as powerful as the 40 MHz 68030 in the Mac IIfx. PowerPC was another step forward, and the 233 MHz G3 in the first Beige G3 was roughly equal in power to a 300-350 MHz 604e CPU, and it soon killed off Apple's top-end Power Mac 9600, which was based on the much more costly 604e chip.

That's the anniversary we're celebrating today, the introduction of the first Power Mac G3. (The first PowerBook G3 had been introduced just days earlier. With a 250 MHz G3, it was the world's most powerful laptop at the time.) Just as the 68040 had allowed Macs to offer more power at lower clock speeds, the G3 brought that level of improvement to PowerPC.

Fast forward to May 1998, and Steve Jobs was ready to show the world the first consumer G3 Mac, the 233 MHz Bondi Blue iMac, which didn't ship until August 1998. Apple rode G3 technology for years, eventually offering a 700 MHz G3 iMac and a 900 MHz G3 iBook.

In August 1999, Apple went to the next level with the Power Mac G4. The heart of the new computer was a modified G3 designed to better support multiple processors and with an onboard "velocity engine", which made it a graphics powerhouse with software that could take advantage of it. That, in turn, lead to dual processor G4 Power Macs in 2000.

The next big step forward was the switch to Intel x86 chips in 2006, followed by migration to Intel's greatly improved Core-i chips (some of which include both Turbo Boost and HyperThreading) over the past year or so, which were on the same order of improvement as the 68040 and G3 were over their predecessors. Frankly, we're not likely to see that kind of performance boost again. Processor speeds get faster slowly, and doubling the number of cores gets more difficult the greater their number.

Of course, that's in the personal computer space. In the mobile processor space, we've only seen one generation of dual-core processors, and speeds currently top out as 1.2 GHz. Quad-core ARM chips are expected in 2012, and we should see them reaching speeds of 1.5 GHz within the coming year, making iPhones, iPads, and their competitors vastly more powerful than today's models. But even they will reach a practical limit in just a few years, barring some radical breakthrough in chip architecture.