Galaxy S8 battery life test, Snapdragon vs Exynos edition: a familiar tale
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While both results mean that the S8 is no "two-day battery" phone like a lot of midrangers with 1080p displays these days, the Exynos would still last you a bit later in the day than the Snapdragon-laden model, with all other things being equal. As to why a 10% or so difference in battery life between the two chipsets, given that they are both 10nm endeavors produced in Samsung's foundries, the answer may lie in the differences in design, as we have custom cores in Samsung's and Qualcomm's silicon, respectively, despite that they are likely still based on ARM's OEM Cortex-A73 and A-53 architecture.
Another reason may be the fact that the Snapdragon cores are clocked higher than the Exynos ones, all eight of them. While the difference in maximum clock speeds for the faster cores is not that big - Samsung lists 2.3 GHz for the Exynos vs 2.35 GHz for the Snapdragon - the low-power cores are clocked at 1.7 GHz on the S8 with Exynos, against 1.9 GHz on the Snapdragon version for the US, and that might be tipping the scales during our demanding battery test, but may also present a difference in endurance when using the phones as your daily driver.
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