The Snapdragon 855 Phone Roundup: Searching for the Best Implementations

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Over the last few years we’ve seen a lot of changes in the mobile market when it comes to the internal hardware of devices. At the heart of every smartphones sits the SoC, which dictates almost every aspect of a device’s experience. Qualcomm has played a major role in shaping the smartphone, thanks to its widely-used Snapdragon platform. The company has had its ups and downs over the last few years, but particularly starting with the Snapdragon 835 from a couple of generations ago we’ve seen some continued and very robust execution from the chip vendor.

This year, Qualcomm’s flagship SoC was the Snapdragon 855. The chip is well known and has been powering the vast majority of Android devices this year, bar a few exceptions. With so many options from various vendors, an interesting question arises: who has managed to do the best implementations in getting out the most out of the silicon? To help settle that question, today we’re doing a smartphone roundup – we're taking a look at device performance from a slew of different S855 devices from various vendors, while investigating how software and hardware designs can change a device’s experience on the very same silicon.

The Snapdragon 855 is Qualcomm’s first chipset to come manufactured on TSMC’s 7nm process node, giving the chipset a much-heightened degree of power efficiency, which in turn enables it to have achieve a high degree of performance.

The chip is powered by a derivative of Arm’s Cortex-A76 and Cortex-A55 cores. Qualcomm markets these as the Kryo 485 cores. The company makes use of Arm’s “Built on Cortex Technology” license which allows vendors to request changes to some of the microarchitectural configurations of the “standard” IP core. In the case of the Kryo 485, Qualcomm has revealed that it has raised the re-order buffer of the core from 128 to a higher undisclosed figure. It’s to be noted that the successor of the Cortex-A76, the A77, comes with a 160 entry ROB, and given that the RTL is still designed by Arm, I’d wager Qualcomm was an early beneficiary of this work. Other improvements are found in the prefetchers which are said to be tuned for more web-browsing type of workloads.

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