Over the past couple of days, rumors have been circling around the web that Apple (NASDAQ:AAPL) is looking into launching new iMac, Macbook and Mac Mini models utilizing quad-core ARM (NASDAQ:ARMH) processors.
A beefed-up Apple ARM chip, coming to a Mac near you?
A couple of years ago it was revealed that a lone Apple engineer was maintaining an x86 version of MacOS X since 2000 in total secrecy, until eventually more manpower was put behind the project and Apple finally shipped its first Intel Macs in 2005.
Many people today seem to believe that history is about to repeat itself and that Apple is on the verge of starting the migration of its Mac computers away from Intel (NASDAQ:INTC) chips. I am yet to see a single rational explanation as to "Why?" and there are several things worth noting that make this scenario extremely unlikely to unfold in the near term.
Further power draw reduction only matters for Macbooks:
While it is true that notebooks as a whole are more important to Apple than desktops, it would seem very strange to undertake a major transition project that would only benefit a part of Apple's Mac line.
ARM processors are generally considered to be significantly more power-efficient than Intel desktop and notebook chips, but is this factor really all that important when the iMac, Mac Pro and Mac Mini don't run off battery power to begin with?
Besides, current Macbooks with Intel chips offer fantastic battery life as it is, with Retina Macbooks and 11" Macbook Airs lasting up to 9 hours and 13" Airs lasting up to 12.
There's really plenty of juice in this thing.
To me, it looks like the reduced power draw of ARM chips is a solution in search of a problem that simply doesn't exist in current Intel chips and those expected to come out in the near-future.
One of the big selling points of the current crop of Mac hardware is compatibility with Windows software, through virtualization or Boot Camp and by moving to ARM they'd lose both. That's something that a non-insignificant portion of the Mac userbase already uses, and it's a big selling point for people moving over from the Windows ecosystem.
In theory, application developers could push out ARM-compatible builds of their OS X software reasonably quickly as the transition to Intel got developers hooked on development tools that can produce "fat binaries," which is a single application package that once built, can run on multiple architectures.
The problem is that they couldn't possibly get every single developer on board with this and even if they somehow did, there is lots of older OS X software that despite having lots of users is simply no longer maintained, yet it works on current Macs just fine. These users would be pretty angry if they bought a new Mac and suddenly their older software no longer works.
If Apple really wanted to further reduce power draw while still maintaining full application compatibility, they could just move from using Intel's laptop chips to the latest Intel Bay Trail chips intended for tablets and smartphones.
Insufficient raw horsepower:
The simple truth is that so far, ARM chips have not offered anywhere near enough the horsepower expected from "real computers." In the charts shown below, the Surface Pro 3 uses a Core i5-4300U from Intel, while the iPad Air uses Apple's own ARM-based A7 chip:
(Source: Ars Technica)
After many years of playing catch-up on the performance front, mobile chips from Intel have now practically managed to catch ARM. The problem is: both still get utterly crushed by performance of Intel laptop chips currently being used by Apple.
(Source: Ars Technica)
And this massive difference is just comparing a top of the line ARM chip to a modern low-power Intel processor. If you were comparing the iPad Air to the Mac Pro placing them on the same chart, the difference would be absolutely staggering.
Theoretically, Apple could move their notebook line to ARM and keep the desktop computers using Intel chips or attempt to offer some differentiation along the lines of "buy this cheap ARM MacBook with longer battery life but less processing power or this powerful Intel MacBook for doing the heavy lifting," but this would be a very un-Apple thing to do.
Besides, nobody ever wants to simultaneously support 2 different processor architectures except during a transition period and Apple is unlikely to be any different in this regard.
Apple very likely learned from its past and there is little doubt in my mind that a secret "MacOS X on ARM" project does in fact exist as a potential backup plan. That's, however, a backup plan; don't expect ARM-based Macs to be launching any time soon.