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.
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.
How Product Marketing Drives the Quad-Core Arms Race
So, if the majority of mobile apps can't leverage four processing cores, why would the industry be shifting to quad-core devices such as the new Galaxy S III? After all, consumers aren't necessarily clamoring for faster devices: One of the world's best-selling smartphones, the iPhone, runs a dual-core processor, eschews support for LTE (the current fastest wireless standard) and includes just 512MB of RAM (not the 1GB that most Android phones feature today).
The bottom line is that consumers don't need quad-core devices as much as hardware makers want us to have them. Competition among Android gadget makers -- each looking to differentiate its products in a cut-throat field of phones and tablets -- is fierce.
And, of course, introducing a new CPU every year helps chipmakers drive profit.
The Exynos chip found in Samsung's new phone is positioned to directly compete with Nvidia's Tegra 3, which was the first quad-core mobile processor on the market. The Tegra 3 is the chip you'll find inside the Acer Iconia Tab, the Asus Transformers Pad and Prime, and upcoming Toshiba Excite tablets.
While Samsung is using its own chips in its own devices, it hopes to build quad-core chips for other hardware makers too.
So far, no smartphone in the U.S. has been released with a quad-core CPU, but that will change sometime in the second half of the year, Gwenapp said. The European and Asian versions of the HTC One X smartphone feature Nvidia's Tegra 3 processor, though the U.S. version of this phone will feature Qualcomm's dual-core Snapdragon chip.
"At this point, quad-core is a marketing-led technology jump. It's an arms race," John Jackson, the vice president of research at the analyst firm CCS Insight, told Wired. "The OEMs are in such a desperate place to sell devices and differentiate on Android that they need a quad-core offering at the top-end of their portfolios even if the performance gain isn't yet there. If you don't have a quad-core device on the shelf and everyone else does, you'll look like you're behind the times."
Rajeev Kumar, a product manager at Austin-based Freescale Semiconductor, agrees that competition for consumer attention is driving quad-core deployment. Freescale, which produces chipsets for e-readers from Sony and Amazon, as well as CPUs for automotive systems and a number of tablets designed for industrial and medical use, will begin producing a line of quad-core processors this summer.
"One of the main drivers of quad-core processor adoption in the consumer space is marketing," Kumar told Wired. "It's very similar to what we saw in the PC market when PCs started switching over from single-core to dual-core processors a few years ago. Some device makers are moving over to quad-core processors because that's the trend."
If You Build It, They Will Come
But battery life is a very real benefit to quad-core processors as well, Kumar said.
"When you distribute power over multiple cores, you can save on power consumption," he said. "If I gave you a 1GHz workload on a single core processor, you'll be using that one core a lot harder to pull off what you're doing. If you have a processor with two, or four cores, you could end up consuming less power because the device won't have to work as hard to handle the workload. So, if engineered correctly, you could end up with better battery life."
Nick Stam, a director of technical marketing at Nvidia, noted that in addition to its four main processing cores, the Tegra 3 has a fifth low-powered companion core designed to handle low-power tasks, such as music playback and running the operating system when it's sitting in an idle state. This further improves battery life.
Nvidia and its rivals, Stam said, are always looking to make products that are more powerful and efficient to help push the industry as a whole forward -- whether app makers are entirely ready or not.
"Build it first and they will come -- that's what's happening here," he told Wired. "It's sort of chicken and egg-ish. There are apps today that people use all the time that take advantage of multi-core processors, dual-core and quad-core. And more are coming to take advantage of quad-core processors because this is where the industry is headed."
While making faster, more advanced processors is great, the chip manufacturers and device makers could help speed up the adoption of quad-core CPUs by providing better development tools to app developers -- tools that could reduce the learning curve of coding for quad-core, Jackson said.
"If you're making apps for Android, you have to build an app that can work on single-core processors, dual-core, now quad-core processors and different screen sizes and graphics processors and amounts of RAM," he said. "It can be tough to figure out what exactly you're supposed to build. The developer facing tools are the missing piece here. If developers had better resources, we'd have a more compelling user experience on quad-core tablets."
