Will Apple  pull the old chip switcheroo again, and embrace ARM CPUs on its Macs instead of Intel silicon? You bet it might, say new rumors , because it could mean your MacBook lasts pretty much all day on a charge.
Only a handful of years ago, Apple abandoned its long relationship with IBM and the PowerPC line of processors for shiny new Intel silicon. The switch from G5 to Intel caused an upheaval of epic proportions among the user community and for the people who code for Apple software--and even required Apple to nursemaid the transition with special dual-mode compatibility code in its OS X for years. But Apple's never looked back, and thanks to a few early-access treats from Intel, and special treatment like the unique one-off processor designed to make the original MacBook Air such a paradigm-breaking machine, the two have kept working together. That may, according to a new and surprisingly emphatic rumor, all be about to change.
SemiAccurate , a publication that was previously correct in predicting Apple would swing away from using Nvidia GPUs, is the source of the latest  rumor . It's based on some insider information, and some smart deductive work: In just a few years, ARM is expected to transition its CPU design to full 64-bit addressing, which would significantly boost the computing power, while retaining the core light power requirements that's a characteristic of ARM's design. A transition to ARM CPUs in two to three years would enable Apple to quickly make use of a whole new class of super-powerful chips that eat batteries much less quickly than competing chip architectures. And it would come just a short while after Apple takes its first steps in incorporating lessons from iOS devices like the iPhone (which runs on an ARM chip) back into its computing operating system OS X, with the latest update into OS X Lion .
And don't forget Apple already has lots of ARM design expertise in-house, thanks to its acquisition of PA Semi for close to $300 million in 2008.
With two more generational tweaks to OS X, and continued development of iOS, Apple could easily make OS X work on ARM chips instead of Intel's. This would also align how code is written for pretty much every device Apple makes. Supplying an emulation system, like it did for the transition to Intel chips inside Macs, wouldn't be difficult, and the fact that Mac apps are now slightly cheaper to buy (thanks to the Mac App Store, and halo effect of the iOS App Store) would mean users wouldn't feel hard done by when, in say four to five years, Apple stopped supporting Intel x68-only software for its ARM-based Macs.
But there's one big reason Apple would want to pull off this trick, which would be timed to the A15 ARM  generation: Mobile computing. There's an undeniable move away from desktop PCs that was initially driven by advances in laptop tech, boosted by the netbook phenomenon, and is now being rocketed into the stratosphere by the tablet PC paradigm. Users now expect ever-more powerful portable machines. And though Intel has teased its next-gen low-power 3-D chip solution, the main reason it's currently shut out of the tablet market is that its chip architecture simply can't compete with ARM chips in terms of power consumption.
The iPad works for around 10 hours on a charge, while the new 11-inch iMacs run reliably into four hours of usage, and Apple's existing bigger MacBook Pros can go up to 7 hours with the Wi-Fi on...all with existing tech. Imagine in 3 years' time, with evolutions in battery design, screen technology (so they consume less power when lit) and solid-state memory advances, a MacBook sporting a low-power-consumption, super-fast ARM chip. Hypothetically, that Mac could run for 18 hours or more on a single charge.
If Apple's desktop Macs ran ARM chips, too, then perhaps they'd need much less cooling--leading to quieter, more efficient power needs. And who wouldn't like to run apps on a top-end Mac Pro with four ARM CPUs aboard, sporting up to 32 separate processor cores?
[Image: Flickr user junesey ]
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