Ready or not, quad-core processors are coming to smartphones and tablets. In fact, the next mobile gadget you buy – particularly if it’s running Google’s Android operating system — will likely pack four CPU cores instead of two.
The latest gadget in this trend, Samsung’s Galaxy S III, was announced in London Thursday. It includes a 1.4GHz quad-core chip, the Exynos 4 Quad, that’s supposed to be more power-efficient — and therefore kinder to battery life — than the rival Tegra 3 quad-core CPU from Nvidia.
The benefits of a quad-core design sound great on paper. But while both Samsung and Nvidia are promising that their respective quad-core chips will turn our gadgets into power-sipping, high-performing computational beasts, industry experts are saying that it will take months, and maybe even years, for the silicon to realize its full potential.
The benefits that can be seen today – speediness in navigating through an operating system, better battery life and improved multitasking stability — are quad-core advantages that most consumers might not even notice without directly comparing dual-core devices and quad-core devices side-by-side. And, so far, very few apps are being built with quad-core processors in mind.
“The key thing for quad-core is that you need the software to make it work,” said Linley Gwennap, principal analyst at the Linley Group research firm. “If the software is optimized for dual-core processors and not quad-core, you won’t see the benefit.”
Single-Core vs. Multi-Core: The Whys and Hows
In their mission to build the perfect processor, chip designers basically have two main goals: stellar number-crunching performance, and battery-preserving power efficiency. To reach their performance goals, the chip makers can increase a processor’s clock speed — but this will reduce battery life.
Perhaps even worse, clock-speed bumps can fry precious CPU circuits if a chip’s design simply can’t handle the load. So how do chip designers reach ever-higher performance goals if they’ve hit a clock-speed barrier?
Simple: They add multiple processing engines, or cores, to a single silicon die. That die might run at a relatively conservative clock speed, but it will have multiple processing engines executing software instructions. And battery life, more or less, is none the worse for wear.
The first multi-core mobile chips featured two processing cores. The new ones feature four cores, allowing for four different operations to be executed in parallel. But having more than one processor core is just part of the equation. Software — whether an app, a game or an operating system — needs to be expressly coded to share its workload among multiple cores at the same time.
Most smartphone and tablet apps currently available are built for devices that run on single- or dual-core processors, and therefore can’t leverage the extra processing power of quad-core chips such as Samsung’s Exynos 4 Quad or Nvidia’s Tegra 3.
The Asus Transformer Prime tablet features a quad-core Tegra 3 chip that helps speed up OS-level operations.
Operating systems, however, are a different matter. Google’s Android 4.0 operating system is coded to leverage four CPU cores, and this can pay off in multiple ways. The entire interface is fluid and zippy, and that can be an important benefit for an OS running home screens packed with visually rich widgets that update in real-time.
Just as importantly, Android can tap into quad-core for OS-level multitasking: While one core loads a browser page, another core can download an app from Android Market, and yet another core can run the OS itself.
But, in general, quad-core support isn’t leveraged by most individual Android apps, which means the chipmaker’s fancy technology often goes to waste.
Nvidia, for one, is well aware that quad-core remains a question mark for consumers, so to promote apps that can highlight the unique talents of quad-core devices, the company has curated Tegra 3-optimized games in its TegraZone website. Going one step further, Nvidia also works deals to pre-load its TegraZone app on devices using the Tegra 3 CPU — an easy prompt that pushes consumers toward Tegra-optimized games
Nonetheless, the majority of smartphones sold worldwide still make use of single-core processors, while dual-core has largely been a feature reserved for mid- to high-end phones, Gwenapp noted.
“Dual-core is still the high-end and single-core, at this point, is still the mid-range, the mainstream,” Gwennap told Wired. “Unless Apple really gets aggressive and puts a quad-core processor in the iPhone 5, I think you still won’t see quad-core becoming more common for another couple years.”
Apple and Research In Motion haven’t announced any plans to deploy quad-core processors in iPhones, iPads or BlackBerry devices — though quad-core iPhones and iPads have been rumored. Microsoft’s Windows Phone operating system confines phones to single-core CPUs, though the next version of the OS will be compatible with multi-core devices of some sort.
But on the Android side of the mobile market, quad-core is the trend. And this trend isn’t fueled by apps, app makers or even consumer demand. It’s fueled by the companies that make the processors, as well as the smartphone and tablet manufacturers that are looking to wow nerd-caliber consumers with impressive specs.