None other than Jean-Louis Gassée says Apple may indeed switch Macs from Intel CPUs to Cupertino’s own homegrown A-series chips:
It looks like I misspoke when I said an An chip couldn’t power a high-end Mac. True, the A7 is optimized for mobile devices: Battery-optimization, small memory footprint, smaller screen graphics than an iMac or a MacBook Pro with a Retina display. But having shown its muscle in designing a processor for the tight constraints of mobile devices, why would we think that the team that created the most advanced smartphone/tablet processor couldn’t now design a 3GHz A10 machine optimized for “desktop-class” (a term used by Apple’s Phil Schiller when introducing the A7) applications?
If we follow this line of reasoning, the advantages of ARM-based processors vs. x86 devices become even more compelling: lower cost, better power dissipation, natural integration with the rest of the machine. For years, Intel has argued that its superior semiconductor design and manufacturing technology would eventually overcome the complexity downsides of the x86 architecture. But that “eventually” is getting a bit stale. Other than a few showcase design wins that have never amounted to much in the real world, x86 devices continue to lose to ARM-derived SoC (System On a Chip) designs.
Apple briefly forked the An line with the introduction of the first Retina Display iPads. The A5 which drove the iPhone 4S wasn’t powerful enough to drive a 3,000,000-pixel iPad screen, so the company added a second GPU to the SOC and dubbed the result the A5X. Six months later, when Apple dropped the iPhone 5 and the second-gen retina iPad, they sported the A6 and A6X, respectively.
Last year’s 64-bit A7, however, is powerful enough that there is no beefed-up “X” model for the iPad. The same chip runs the latest iPhone and both flavors of iPad. The A8 is expected to debut inside the iPhone 6, and the new iPad Air and Mini next month. That will make five generations of ARM SOCs Apple has designed in-house, and each model has been the best-designed ARM chip of its time — or very close to it. As of yet there’s nothing else as good as the A7, and nobody is going to even match it before the A8 comes out.
So the question in my mind isn’t if Apple can design something powerful enough to run a desktop-class computer, or even a workstation. The question instead might be how soon Apple decides to pull the trigger, and how bumpy the transition period would be.