Qualcomm has dabbled in 64-bit ARM chips a bit, but today is the first time the company has brought ARM's new architecture to its flagship Snapdragon 800 line. The Snapdragon 808 and 810 are the high-performance counterparts of the previously announced 410 and 610 systems-on-a-chip (SoC), but this probably isn't Qualcomm's true next-generation ARM play. While 808 and 810 are clear steps forward, Qualcomm is compromising by making these chips without the custom components it's known for.
To understand what makes the 808 and 810 unusual for Qualcomm, you have to know a little about ARM licensing (it's not actually as boring as it sounds). ARM designs reference CPU cores with the Cortex branding, which companies like Samsung, Qualcomm, and Nvidia license. However, ARM also creates the ARM instruction set which can be used to make ARM-compatible cores with extra features.
Licensing the instruction set is expensive -- likely in the tens of millions of dollars range. Both Qualcomm and Nvidia have ARM instruction set licenses so they can design and implement their own CPU core designs. In the case of Nvidia, it is planning to release the project Denver core later this year in a version of the Tegra K1, but Qualcomm has been designing its own custom Krait cores for years. Krait has a few features that you don't find in normal ARM chips, like dynamic clock speed adjustment. However, it takes time to develop Krait cores, and ARM does offer those tempting ready-made Cortex CPUs.
With Snapdragon 808 and 810, Qualcomm is taking advantage of ARM's stock 64-bit solution. ARM's 20nm Cortex-A53 and -A57 are the 64-bit versions of the A7 and A15 you're probably more familiar with. These two cores work together as separate CPU islands on a single chip to offer a combination of high-performance (A57) and high-efficiency (A53). ARM calls this a big.LITTLE configuration, and you see it most often in Samsung ARM chips. Because the Krait cores can adjust their speeds as needed, Qualcomm doesn't use big.LITTLE in most of its chips -- the 808 and 810 aren't Krait, though.
The Snapdragon 810 runs four A53 cores and four A57 cores in big.LITTLE. It also supports LPDDR4-1600 RAM (as opposed to LPDDR3), Bluetooth 4.1, 802.11ac, and cat 6 LTE. This SoC also debuts a new Adreno 430 GPU with up to 30% more power than the Adreno 420. The 810 can power displays up to 4K resolution thanks to all that power. A bit more down-market is the 808, which is a hexa-core big.LITTLE chip consisting of four A57s and two A53s. It supports LPDDR3 memory, Bluetooth 4.1, and cat 6 LTE. This version has a new Adreno 418 GPU that can power a 2K display and is about 20% more powerful than the Adreno 330 in the Snapdragon 801.
Because these SoCs run the newest ARMv8 instruction set for 64-bit support, they also have a few additional power efficiencies not seen in older 32-bit parts. However, Android doesn't really support 64-bit computing yet, so this aspect is mostly marketing fluff for the time being. The fact that Qualcomm is building chips with standard off-the-shelf ARM cores probably says something about how blindsided everyone was by the Apple A7 with its 64-bit Cyclone core.
The Snapdragon 808 and 810 aren't expected to arrive in devices until early 2015, which likely means they are destined for Asia. Qualcomm has spoken previously about the appeal of processors with more cores in Asian markets, and these SoCs are certainly packed full of them. The Snapdragon 805 is probably a little faster than the 810 despite being 32-bit, but it runs super-powerful Krait 450 cores. Having more bits isn't everything -- 64-bit Krait cores will come in time. Personally, I would worry more about the state of 64-bit support in Android and Windows Phone -- hardware is nothing without the requisite software, after all.
