Subject: Processors, Mobile
Manufacturer: Apple

A New Standard

With a physical design that is largely unchanged other than the addition of a glass back for wireless charging support, and featuring incremental improvements to the camera system most notably with the Plus version, the iPhone 8 and 8 Plus are interesting largely due to the presence of a new Apple SoC. The upcoming iPhone X (pronounced "ten") stole the show at Apple's keynote annoucement earlier this month, but the new A11 Bionic chip powers all 2017 iPhone models, and for the first time Apple has a fully custom GPU after their highly publicized split with Imagination Technologies, makers of the PowerVR graphics found in previous Apple SoCs.

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The A11 Bionic powering the 2017 iPhones contains Apple’s first 6-core processor, which is comprised of two high performance cores (code-named ‘Monsoon’) and four high efficiency cores (code-named ‘Mistral’). Hugely important to its performance is the fact that all six cores are addressable with this new design, as Apple mentions in their description of the SoC:

"With six cores and 4.3 billion transistors, A11 Bionic has four efficiency cores that are up to 70 percent faster than the A10 Fusion chip, and two performance cores that are up to 25 percent faster. The CPU can even harness all six cores simultaneously when you need a turbo boost."

It was left to improvments to IPC and clock speed to boost the per-core performance of previous Apple SoCs, such as the previous A10 Fusion part, which contained a quad-core CPU split in an even arrangement of 2x performance + 2x efficiency cores. Apple's quad-core effort did not affect app performance beyond the two performance cores, with additional cores limited to background tasks in real-world use (though the A10 Fusion did not provide any improvement to battery life over previous efforts, as we saw).

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The A11 Bionic on the iPhone 8 system board (image credit: iFixit)

Just how big an impact this new six-core CPU design will have can be instantly observed with the CPU benchmarks to follow, and on the next page we will find out how Apple's in-house GPU solution compare to both the previous A10 Fusion PowerVR graphics, and market-leading Qualcomm Adreno 540 found in the Snapdragon 835. We will begin with the CPU benchmarks.

Continue reading our look at the performance of Apple's A11 SoC!