The same leak doesn’t talk about any clock speeds, but one can assume that there are four faster and more powerful and four slower cores, something that you saw with the Snapdragon 810 and the Snapdragon 600 series. A Chinese source includes the fact that this is a 10nm FinFET processor and has a Snapdragon X16 Gigabit class modem. These two things have been officially confirmed by Qualcomm.
The roadmap details Adreno 540, obviously, with faster GPU support for 4x LPDDR 4x @ 1866 MHz memory. The new Snapdragon 835 (also called MSM 8998 internally) supports UFS 2.1 storage and it is supposed to arrive in Q1 2017. The source is quite confident that you can expect to see this SoC inside some versions of Samsung Galaxy S8 phones.
Snapdragon 660 is clearly a successor to the recently launched Snapdragon 653. The Snapdragon 653 comes with four Cortex A72 with speeds up to 1.95GHz and four Cortex A53 for power saving. The new Snapdragon 653 supports a few important features that will drive phone sales in the mainstream part of the market in 2017. The Snapdragon 653 has a Snapdragon X9 Cat 7 modem with 300 Mbps downlink speeds and 150 Mbps uplink speeds, dual cameras, and supports 8GB of RAM.
This is what you will see in mainstream phones in early 2017. Let’s not forget the Qualcomm upload plus. It comes with 2x20MHz carrier aggregation and 64-QAM modulation on both upload and download side. We think 8GB will be very big for mainstream and performance phones, but of course is pure marketing and very little to do with need or necessity.
According to the leaked roadmap, the information about the chip potentially called Snapdragon 660 are all over the place. First they called it the MSM 8976 Plus and Qualcomm shared on its website that the Snapdragon 653 also shares a 8976 Pro internal branding. The Snapdragon 660 and 8976 Plus might be two different chips. In any case they would come to replace the Snapdragon 653 / 652 SoCs.
The roadmap also claims that the MSM 8976 Plus chip comes with Kryo 4x4 configuration while the Snapdragon 660 comes with Cortex A73 quad core with four Cortex A53s. It would make a lot of sense to see the 14nm Cortex A73 quad core with four Cortex A53 cores. The GPU is updated to Adreno 512, while the Snapdragon 653 comes with Adreno 510. The 14nm makes sense as it will offer a lot of power savings compared to the Snapdragon 652 and 653, both based on a 28nm manufacturing process.
We would not expect to see Snapdragon 660 and mysterious MSM 8976 Plus before the middle of next year at the earliest, but the roadmap also claims that the new chip comes with Snapdragon X10 300/ 150 Mbit capable LTE Category 13 (uplink) LTE Category 7 (downlink) modem.
Last and not least, the new MSM 8976 Plus might support UFS 2.1 storage and 2x LPDDR4 4X at 1866 MHz.