By Tasawwar Rahman (’22)

Just 14 years ago, Apple transitioned its Mac chipsets from PowerPC to Intel, spurring onwards a decade and a half of unparalleled success. Now, once again, the Mac prepares for its biggest change yet as it gets ready to move on from Intel to newer more efficient ARM-based chips next year. In their highly-anticipated Worldwide Developer Conference next month, Apple is expected to announce the change which presents many unique but necessary challenges and promises to prepare the Mac for the coming decades.

For Apple, this change, however, isn’t one they take lightly. After all, changing the processor architecture means that every app needs a software update at best, or is downright incompatible at worst. It was a careful consideration and to understand it, we must recognize the differences between the CISC architecture that powers Intel and the RISC architecture that powers ARM. 

In a nutshell, the fundamental difference between the two is the size of the instruction or tasks your device’s compiler sends to its processor. With RISC or Reduced Instruction Set Computer, all instructions must be completed in one clock cycle. In contrast, CISC or Complex Instruction Set Computer, a wider variety of instructions can be executed over multiple clock cycles, which allows the device to carry out complex instructions without as heavy use of a compiler. The benefit of RISC is that its transistors are more general allowing for smaller chips thus giving better power and thermal efficiency. Furthermore, because all actions are carried out in one clock cycle, the processor is faster for the majority of tasks and takes about the same amount of time for the complex compound ones.

But beyond just the purely technical aspects of ARM or Advanced RISC Machine chips, it makes sense for Apple in a lot of ways as part of their broader strategy. Throughout its history, Apple has always sought to control all aspects of its products. This is evident from its own operating systems to their closed-off ecosystem. However, the computer microprocessor is the only aspect where Apple is truly beholden to another company; and worse to Intel which notoriously underperforms and fails to meet deadlines. And in terms of chip development, Apple brings a lot to the table with its cutting edge ARM-based chips years ahead of its competitors, and for half the cost of Intel chips. The rumored 5-nm process ARM chip is a game-changer bringing with it a reported 12 cores, double that of a fully specced out MacBook Pro. The iPad Pro has shown remarkable, yet underutilized, performance with its last-gen boasting an 8 core A12X Bionic chip that is faster than 92% of PC laptops and has the graphic power of an Xbox One S. 

Even more so than seeking independence from Intel, an ARM-based Mac fulfills Apple’s long term vision of a unified App Store, bringing with it access to 2 million iOS apps along with an iPad that can truly replace your laptop. An ARM-based Mac running the same architecture and A-series chips that power an iPad Pro is capable of sharing the same codebase. This would allow for the further proliferation of mobile apps to the Mac and more importantly Pro level apps to the iPad. A common architecture would allow for a common development experience, similar to the process of making iPhone and iPad apps, in turn jump-starting Apple’s lagging Mac App Store and providing a richer user experience.

While Apple routinely uses the element of surprise to create hype for its products, switching an entire chip architecture is by no means a quick move, this change was long in the making. In fact, Apple has been laying the groundwork for this shift even if you haven’t realized it. At its last Worldwide Developer Conference, Apple announced several updates foreshadowing its future moves. The first being the release of Project Catalyst, which allows developers to begin the process of porting iPad apps to Mac with the press of a button. More significantly, macOS Catalina only supports 64-bit apps that can leverage more RAM  required for RISC chips. 

Overall, the adoption of an ARM-based Mac is an exciting step towards the future, a future where the lines between mobile and desktop become blurred, and where we see more powerful and smaller devices than ever before. This is by no means an easy transition, but if Apple’s track record says anything, it will be a painless well-planned one. And unlike the failure of the Surface Pro X, a smooth transition to ARM could be the necessary impetus for a future of not just Apple but the universal adoption of ARM desktops. Apple, who controls all aspects of its devices, is in a position to do just that, and in the process change personal computing forever.