Snapdragon vs. Hummingbird vs. OMAP - the mobile CPU war beyond 1GHz
1GHz processors on high-end handsets are all the rage now, but 1.5GHz puppies with more than one core have finished sampling and are being shipped to manufacturers. These are already desktop clock speeds, but how much is enough? Will the mobile CPU war fall victim of the same delusion the desktop one had – that faster is better? Or will it try to find the sweet spot between raw power and energy consumption as their laptop counterparts did?
We think the answer will be known sooner rather than later as we've already attained the magic 1GHz number, and the upcoming CPUs promise even higher clock speeds with the same power consumption. Hummingbirds and Snapdragons - these 1GHz animals are offering all-in-one solutions to cell phone manufacturers. Called system-on-a-chip (SoC), they take care of both the system tasks and the hardware video acceleration, often along with all baseband and RF connectivity, the GPS module and the multimedia processing. They are designed to fulfill the longest lasting dream of any electronics user – to carry one device that does it all decently.
Qualcomm, Samsung, Apple and Texas Instruments are currently the major SoC players, and they have something in common – all of their chipsets are based on the ARM architecture. ARM Holdings owns the intellectual property rights on processor architecture; they develop the next generation’s schematics, and then sell them to chip manufacturers to come up with their own custom SoC solutions. The current 1GHz mobile CPUs are based on ARM's Cortex-A8 generation, but Cortex-A9 is just around the corner, and it is exciting.
Qualcomm's Snapdragon family is probably the household name when it comes to 1GHz mobile CPUs. It's been around for more than a year now, shining initially in the Toshiba TG01, then powering such prominent phones as the HTC HD2, the Nexus One and the HTC EVO 4G. The Snapdragon's Scorpion core takes care to add better multimedia instructions and power management to the Cortex-A8 core of ARM Holdings.
The prevailing concern for the company was to make a mobile SoC that can go all day on a single charge, thus Snapdragon was designed with low power consumption in mind. For the graphics tasks, Qualcomm relies on the AMD Z430 processor after purchasing Imageon - the mobile graphics department of AMD, then rebadged their GPUs (originally developed by ATI) under the Adreno moniker. This first generation of Snapdragon is produced with the older 65nm technology, which fits less transistors on the same space than the new, upcoming iteration of these chips, manufactured with the 45nm process.
The third generation of the ubiquitous Snapdragon is the most interesting one, of course. The MSM8260 and MSM8660 chipsets for high-end smartphones will be dual-core, with each core running at up to 1.2 GHz. Even faster version supporting larger screen resolutions is QSD8672 – two cores humming at the sweet 1.5GHz, which will most likely go into tablets, or the likes of the Dell Streak. Qualcomm has the advantage of having finished the sampling of its next generation SoCs, and HTC is rumored to be the chief beneficiary, so they might be first to deliver a smartphone with two processor cores.
What do these dual Scorpion core Snapdragon chips promise for us spoiled brats waiting on the shiny new toy? Full HD 1080p video recording and decoding plus dedicated low-power audio engine for multichannel home-theater surround sound, for starters. Add to that a GPU subsystem based on the new Adreno 220, and capable of up to 80mln triangles per second for enhanced 3D gaming plus an integrated low-power GPS. All these “low-power” adjectives are not coincidental - the third generation is supposed to use 30% less energy than the single core Snapdragons, also because the work will be evenly distributed between cores.
A chief differentiation of Qualcomm for their Snapdragon architecture is to make it a truly all-in-one solution for the various tasks on a modern smartphone. After spending more than a decade in CDMA devices, its baseband modem chips are now integrated in the Snapdragon SoC, saving manufacturers the effort to add third party silicon. The MSM8660 Snapdragon will even support both multi-mode HSPA+ and 1xEV-DO Rev - a true world phone with dual-core prowess.
Samsung Hummingbird and Apple A4:
The next-gen Snapdragons above will be produced with the 45nm technology, but there are actually phones on the market with CPUs that utilize this technology right now. Enter Samsung’s Hummingbird chipset, a SoC which powers the company’s first bada OS phone – the Samsung Wave, and the Galaxy S with its US carrier versions.
The main added value of Samsung’s Hummingbird chipset, compared with the other current hardware platforms, though, is said to be in the graphics subsystem. It is built around a PowerVR SGX 540 core, and Samsung claims a theoretical processing of up to 90mln triangles per second. The 2D performance of the Hummingbird is better with an even larger margin – a billion pixels per second versus half a billion for the dual-core Snapdragon.
It is not entirely clear for us how the chipset manufacturers are reaching these speeds, but the end result is outstanding, and on par with what mobile gaming systems are achieving. The iPhone 3GS, however, has the previous version of the PowerVR chips, and still managed to run the most enticing 3D titles ever to appear on a small screen, so it is all up to game developers now to take advantage of the new raw speeds.
The 3GS successor, the iPhone 4, is having a custom designed chipset called A4, which is running the iPad as well. Samsung developed the Hummingbird platform based on intellectual property from Intrinsity, a processing solutions company that Apple bought last year for $121 mln to lock in the A4 exclusivity for its own mobile gadgets. Therefore, when dissected, both Hummingbird and A4 share a lot of commonalities, and we’d assume they are fairly similar in basic capabilities too.
As if to back up these suspicions, the Samsung Galaxy S with its US carrier versions, and the iPhone 4 occupy the top two places in the graphics GLBenchmark 1.1 test. The acquisition of the fast chip designers by Apple hasn't severed the ties with Samsung, as they are still contractually obliged to support the Hummingbird platform.