Since Apple introduced the Macintosh in 1984, Macshave used three different CPU families. First was the Motorola 680x0family, and it was followed by the PowerPC, which Apple helped developin conjunction with Motorola and IBM, in 1994. Thanks to 680x0emulation built into the Mac OS, PowerPC Macs were able to run most680x0 apps.
In June 2005, Steve Jobs announced that Apple would switch fromPowerPC to Intel "within the next year", and the first Intel Macsarrived in January 2006. Once again, the operating system had software,known as Rosetta, that allowed new Macs to run apps designed for oldMacs. Apple continued to include Rosetta as part of OS X until OS X 10.7 Lion was introduced this pastJuly, at which point PPC support vanished and several important legacyapplications (most notably Quicken) were left behind.
Lately there have been rumors that due to the success of itsiDevices, which are now built around an ARM processordesigned by Apple, we're going to see Macs move from Intel to ARM,probably starting with the MacBook Air within a year. This week Low EndMac's staff discusses the pros and cons of such a switch.
Austin Leeds (Apple Everywhere):Whether I believe the ARM rumors or not is moot. I do, however, believethat Apple has been planning to switch to ARM for some time. Thearchitecture is not quite advanced enough to power the latest Macs yet,but its progress has been stunning over the past five years. With theirdiminutive size, power-consumption, and heat production, Apple's Aseries CPUs could easily be grouped in sets of 8, 12, 16, 24 - whateverit takes to match the Intel CPUs.
The pros of such a switch would be independence from Intel's releasetimetables, and the rendering of pointless the argument that "Macs arejust overpriced PCs with a different OS". If Macs could show a genuineincrease in performance with the A series CPUs, like they did in thePPC days, then Apple would have that much more in the way of braggingrights.
The cons? Compatibility and reliability. I haven't experienced anyproblems with my A4, but that's not to say that a group of themwouldn't have some serious issues working together. Compatibility couldbe overcome with another emulation system such as Rosetta, but sinceIBM now owns the technology that drives Rosetta (and arguably forcedApple to kill Rosetta), it remains to be seen how Apple will pullanother emulator out of thin air.
Dan Knight (Mac Musings): I am veryskeptical of Apple moving Macs to ARM in the short term, primarilybecause ARM processors simply don't offer sufficient power at presentto replace even the slowest 11" MacBook Air with its 1.6GHz Intel Core i5 CPU, although a dual-core ARM processor may be ablecompete with the Intel Atom, a processor used in many netbooks. (Baseon benchmark results published on Android Authority, the A4 was about30% more powerful than the fastest competing dual-core ARM chips.)
Apple's A6 is rumored to be a quad-core processor, and when it shipswe may finally see an Apple A series processor pass the 1 GHz mark, butthe fastest ARM chips today seem to be 1.2 GHz, which is just a 20%boost. Couple that with four cores, and you could end up with enoughpower for a notebook computer - but still not as much as the slowestMacBook Air.
Further, ARM is a 32-bit architecture, which is limited to 4 GB ofmemory space. Every Mac made today has a 64-bit CPU and runs 64-bit OSX Lion, so moving to ARM would be a significant step backwards in anage where 6-8 GB of system memory is becoming more common. I just don'tsee that happening.
I don't see any reason that Apple couldn't or shouldn't produce aniOS notebook, especially with the quad-core A6, but I don't see any wayfor Apple to move Macs to ARM until there's a 64-bit version. At thatpoint, with sufficient memory space and cores and clock speed, ARMcould emulate Intel sufficiently well to make such a transitionpossible so Mac users wouldn't have to leave all their software behind,which I see as a very significant factor.
At present, the added bonus of Intel Macs is the ability to runWindows and apps for Windows. Although Windows 8 will be available forARM, I don't see that becoming a significant option because existingWindows software used on the desktop is universally written for Intel'sx86 processors.
Tim Nash (Taking Back the Market): Oneof the biggest reasons for staying with Intel for Macs is Windowscompatibility. An increasing number of MacBook Airs and Pros are soldto people who want a well built laptop that is properly supported bythe manufacturer, runs Windows well, and doesn't come laden withcrapware. Even if Windows 8 runs well on ARM, there will be plenty ofpeople and organisations that want to run legacy Windows apps on goodhardware that is Intel based, because they rightly feel there will beno significant gain from trying to get old software running on ARM.
From Apple's point of view, Macs and MacBooks are still veryprofitable and are increasing their unit sales, revenue, and marketshare Year on Year with updates of components and OS X, but with littleneed to radically change the form factor. Macs as they are havebecome a cash cow that Apple should continue to milk for as long asthere is a PC market.
Simon Royal (Tech Spectrum): Therehves been a lot of rumours of Apple moving towards the portable devicemarket with the iPhone/iPod/iPad, and with the whole move with Lionlooking more like iOS, it is easy to see why.
I don't see Apple ditching their Macs just yet. I do see ithappening possibly in a few years time when the portable market hascaught up in terms of power.
The whole of the computing world seems to be moving towardsportable, what with smartphones being more advanced, and netbooks andtablets becoming faster and more powerful. This is true not only ofApple, but Dell, Microsoft, Blackberry, and many others too.
I don't see the benefit for Apple to make yet another platform jump.Okay, most smartphones already run on ARM processors (Android, Symbian,and iPhone), and Apple's portable range already runs on ARM technology,but like others have already pointed out, it is too underpowered toreplace the current range of Macs.
If Apple were to jump to another architecture again, this wouldalienate those who liked dual-booting or virtualising Windows -something that has been a big bonus to Intel owners. It would also meanyet another Intel to ARM Universal Binary situation, and thisarchitecture hopping could put off software developers, as some of themhave already had a hard time switching from PPC to Intel.
Personally, I think Apple might be planning it. They might belooking to move from big powerful Macs to small portables running onfuture high powered ARM devices running the iOS across tablets,laptops, iPods, and phones.
With the exception of the MacPro,all of Apple's desktop Macs have gotten smaller. Apple has justditched the MacBook. Nowwe have even smaller Macsminis and ultra thin iMacs,and the MacBook Air isabout as thin as you get.
Could this be Apple downsizing its devices? Could they be needing topull away from Intel quickly? Could we see a shift in Apples direction,especially without Steve Jobs at the helm?
Charles Moore (severalcolumns): I would rate the likelihood of ARM-powered Macs inthe future as very strong to inevitable. There have been seeminglyplausible reports that Apple has been testing potential use of itsin-house designed A series of ARM processors in future MacBooks,especially once a quad-core A6 ARM chip, expected to be ready sometimenext year, is ready.
A China Economic News Service report bySteve Chuang recently reported that Taiwan Semiconductor ManufacturingCo., Ltd. (TSMC), reportedly the worlds largest semiconductor foundryby market share, has started trial production of the ARM-based A6processor in cooperation with Apple, with the production design to befinalized in the first quarter of 2012 and to be publicly unveiled inQ2/12 at the earliest. It is speculated that Apple's mid-term plan willbe to eventually power at least its smaller, lighter Macs, presumablybeginning with the MacBook Air, with A6 silicon.
This prospect is being taken seriously by Intel. In an interview with CNET's Brooke Crothers,Intel's Ultrabook group director Greg Welch affirmed that it would beimprudent for Intel to to be dismissive of the ARM in Macs rumors, butin the meantime they'll continue to innovate so Apple will continue toconsider them as a CPU supplier - but Intel will also be hedging itsbets with continued development of the Ultrabook platform.
Advantages for Apple in migrating Macs to ARM, aside from greaterin-house control over product engineering and lower costs, would besmaller-sized components that would facilitate making their computerseven thinner and with improved battery life. Downsides would includethe probable necessity of a major OS X rewrite, and likely backwardsoftware compatibility issues that would make the troubles caused by OSX 10.7 Lion's dropping Rosetta PowerPC emulation look trivial. Evenmore problematical would be the probable loss of Windows compatibility,which has been such a key factor in Apple's market resurgence since themigration to Intel silicon in 2006. A workaround for that might be ahybrid CPU with tandem x86 and ARM processor cores, with Intel havingreportedly affirmed willingness to consider working with Apple onprojects like that.
Personally, I think it's more a matter of when thanif, and the first wave of OS X/iOS convergence represented byLion is an indicator of what's coming.
Adam Rosen (Adam's Apple): Thedecision to switch to ARM will likely be made on two primary factors:whether the design offers a roadmap for continued performanceimprovement with lower heat and power consumption, and whether thechips can be manufactured in high enough volume to supply Apple'sneeds. Both of these issues are what drove the change from PowerPC toIntel.
If Apple does make the change, we're faced (again) with legacysoftware compatibility issues: existing Mac software as x86 binaries,and Windows compatibility for the same reason. A fantastic side benefitof Apple switching to Intel chips has been Windows compatibility,through Boot Camp and virtualization software. The latter is verypopular, with many of my business clients running Parallels or VMWareon their Macs. This feature alone has sold many Macs to new users, itwould be foolish to remove this capability.
If everything "just works" for end users, either CPU architecture isadequate. But if Apple switches to ARM and then pulls anotherRosetta-killing stunt, the headaches for Mac users might causedefections - either to Windows, or to an iPad with iOS.
Dan Bashur (Apple, Tech, andGaming): ARM CPUs are powering devices running iOS with thegreatest of ease. In addition, without the heavy demands of Flash, theweb-driven content we typically consume on more powerful platforms isdelivered to these lower powered devices in virtually the same qualitythrough HTML5. The days of Flash being relevant became numbered as soonas Apple pulled the plug on it for iOS devices. Going forward, I wouldnot be surprised if newer Macs begin to follow suit and eliminate Flashaltogether, as well with future versions of OS X. [Flash is notincluded with OS X 10.7 Lion.]
Meanwhile, as ARM CPUs become more and more efficient, and withApple's dependence on Intel to deliver CPUs that fit into their productdesigns, it becomes more and more obvious that the proverbial writingis also on the wall for Intel. Just look at the heat being emitted fromthe latest Core i7 MacBook Pro! When a device is running hot enoughinternally to boil water (the i7 quad core mobile CPU is designed torun up to 105 degrees C within spec), the design is clearly flawed andnot built properly to be in a portable device.
Intel is currently scrambling to come up with more efficientultra-low power solutions (in addition to the ultra-low power Core 2Duo and i3), but ARM has a huge lead in miniaturizing this technology,while improving on it at a much faster pace as they continue to meet(and possibly exceed) Apple's needs in iOS devices. I envision a futurewith clusters of ARMs running in tandem to power Macs similar to howthe PlayStation 3 was built with IBM's Cell processor technology.Octo-core ARMs are right around the corner, and with Nvidia's Project Denver, it's clear the the scales are tipping in favor ofARM in higher powered and more graphically demanding applications. WhenARM is able to overcome the 64-bit hurdle and embed that kind oftechnology into their processors, the time will come when Apple andIntel part ways.
