Intel recently backed up Apple's claim that 2003 is the year of the portable. Intel's new Centrino lineup introduces the Pentium M processor, the first Intel chip designed from the ground up for mobile systems. Traditionally, Intel's laptop chips have been "diet" versions of their desktop chips. While features like Speed Step help increase battery life, Intel (and AMD for that matter) based laptops just haven't been able to keep up with PowerPC based laptops.
PC Magazine's April 8th issue has a round up of the various new Centrino laptops coming to market. To be considered a Centrino system, a portable must pack the new Pentium M as well as a new Intel chipset that stresses wireless technology. Laptops are already being released by Acer, Dell, Gateway, and several other major players in the market. The price point on the new systems is quite a bit higher than many other portables on the market at this point (and even some Tablet PC systems).
The Pentium M is actually an interesting venture. Prior to the Pentium M, the only other major processor designed specifically for portables was Transmeta's Crusoe. If you're not familiar with the Crusoe chip, it's a hybrid processor that is half hardware and half software. The back end (the part that actually handles the calculations and processing) of the processor is the hardware portion, while the front end (the portion that handles scheduling) is based in software.
I have not yet seen a comparison that specifically makes use of Crusoe based laptops and Pentium M laptops. However, judging by the benchmarks I've seen for them on an individual basis, I'd guess that the Pentium M will out perform a Crusoe, but doesn't get as much battery life as a Crusoe system.
The big concern as Mac users is how the battery life will compare to Apple's portables. It's long been considered an unwritten rule that if you wanted good battery life you should choose an Apple portable. The PowerPC processor uses far less battery power than the traditional x86 processor. While definitely not the only factor in determining battery life, most other components of Apple and x86 laptops are quite similar in design and power consumption.
Intel claims a battery life that's better than five hours. In contrast, Apple's new 12" PowerBook claims a battery life of up to five hours. I don't know about anyone else, but I've never actually gotten results even close to that. I have a 15" TiBook 800MHz and tend to get just about three hours of battery life with normal use. I'd be interested to hear how long Pentium M users are able to go without a recharge in normal use. If we go by what the manufacturers suggest at this point, it appears that the new Pentium M based machines are getting better battery life.
Performance wise, a Pentium M machine at 1.4 GHz will best a Pentium 4 M at 2.4 GHz. Impressive, especially considering the lower power consumption. Almost makes you wonder why they don't strap these puppies into desktops so we can cut down on the number of power plants out there. My initial thoughts when I heard the name of the new processor is that it convolutes the Pentium branding. It's easy to see how people will become confused between a Pentium M and a Pentium 4 M. Two very different processors, but with names differentiated by a single character.
In addition to this, bringing in the Centrino name blurs things even further. A laptop with a Centrino label has a Pentium M processor, but apparently not all manufacturers are including the Intel Centrino chipset, which is an essential part of the platform. These half-Centrinos are shipping with the exact same label as the true Centrinos. Buyer beware!
John Dvorak, columnist for PC Magazine, recently made some conjecture about an Apple Switch to Intel based processors. He points to various interactions between Apple and Intel over the past year or so. I'd like to just respond to this a bit, since I feel quite differently on the matter.
Apple was one of the original companies to help develop and nurture the PowerPC platform. They have spent years and millions of dollars in creating a market for the chip through their systems. They have given countless presentations on the "Megahertz Myth" to help explain how clockspeed isn't a true indicator of performance, helping to alleviate buyer concerns. Apple has a strong interest in the PowerPC processor and it is as much a part of today's Macintosh experience as a one button mouse.
A few months ago, many of the Apple rumor sites started running stories about how Apple was going to switch to using AMD processors. The rumors pointed to close ties between Apple and AMD, various common public appearances, etc. The same kind of ties that John Dvorak pointed out in his Apple Switch article. Apple keeps ties with many manufacturers on a variety of projects (e.g. Apple and AMD are both part of the HyperTransport consortium). This is normal behavior, not a sign of such a major change.
With the PowerPC 970 just around the corner, I don't see Apple switching to an x86 architecture. While it is true that many of the other components inside a Macintosh are quite similar to an x86 machine, Apple's stance is more political than technical. Apple has long kept a tight hold over the Macintosh architecture, which these days essentially encompasses the processor and chipset. Almost every other component in a Macintosh system is compliant with the same standards x86 manufacturers use for their systems.
The reason Apple keeps such a tight hold over the core of the Macintosh is to maintain the Macintosh's legendary stability. By having such specific basic hardware to work with, Mac OS X runs rock solid. I've often thought that the reason the Windows platform is so unstable is the fact that Microsoft has to write code for thousands of different processor and chipset combinations (well that and a bunch of legacy hardware and software, but I digress). Mac OS X runs on far fewer variations in hardware, helping not only with stability, but with performance (okay, in theory).
The biggest hurdle in moving your customer base to a completely different processor ISA exists in end user applications. While it is quite true that Mac OS X could easily be ported to x86 (if it hasn't been already), thousands of other Macintosh applications would have to be recompiled or rewritten to run on the different processor. Let's be realistic, not even all of the popular applications have been moved to Mac OS X yet.
Some of you might be thinking "well, why not just port the Windows stuff over?" The issue there becomes one of libraries. There is nothing like Cocoa or Carbon on Windows. Windows applications would have to be completely rewritten to run on an x86 version of Mac OS X as well. A move to x86 would require a lot of effort by both users and developers that I just don't think Apple is willing to risk forcing.
Moving to the 64-bit PowerPC 970 from IBM would basically require a recompile and some small changes of Mac OS X only. The PPC 970 can handle 32-bit code (current Mac OS X) as well as 64-bit code, as long as the operating system knows how to handle both. While end user applications would all require the same recompiles and small changes, the immediate gain of having 64-bit processing in your application is minimal at best. Applications probably wouldn't move to 64-bit except in a "why not?" kind of approach.
The biggest advantage of moving to the PPC 970 doesn't come from the fact that it's 64-bit, but its higher clockspeeds. The latest reports from IBM are talking about the processor coming out with a clockspeed topping out in the 2 GHz range. This is obviously a fairly big jump from the current 1.4 GHz G4. In addition to higher clockspeeds, the PPC 970 has a lot of interesting designs to help get more work done per clock cycle than our friend the G4e. For some great information on this, I recommend John Stoke's article on IBM's PowerPC 970.
So, I do see Apple making a processor change, most likely this year even. I predict however, that it won't be to an AMD or Intel processor, but to the more logical PowerPC 970. While it won't be the fastest processor on the market either, it will definitely be a breath of fresh air for the platform. Apple is currently preparing their product line for a new processor. The G3 remains in only a single system (the iBook). Expect the PPC 970 (not sure if it will be branded the G5) in PowerMacs first, then the high end PowerBooks. The G4 will be in the "i" line of products for some time to come.
Jason Deraleau works as a systems administrator by day, IT consultant and technical writer by night, and is the coauthor of the upcoming Running Mac OS X Tiger.
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