iPhone 6 and Apple A8 SoC Performance Preview
One Small Step
While most articles surrounding the iPhone 6 and iPhone 6 Plus this far have focused around user experience and larger screen sizes, performance, and in particular the effect of Apple's transition to the 20nm process node for the A8 SoC have been our main questions regarding these new phones. Naturally, I decided to put my personal iPhone 6 though our usual round of benchmarks.
First, let's start with 3DMark.
Comparing the 3DMark scores of the new Apple A8 to even the last generation A7 provides a smaller improvement than we are used to seeing generation-to-generation with Apple's custom ARM implementations. When you compare the A8 to something like the NVIDIA Tegra K1, which utilizes desktop-class GPU cores, the overall score blows Apple out of the water. Even taking a look at the CPU-bound physics score, the K1 is still a winner.
A 78% performance advantage in overall score when compared the A8 shows just how much of a powerhouse NVIDIA has with the K1. (Though clearly power envelopes are another matter entirely.)
If we look at more CPU benchmarks, like the browser-based Google Octane and SunSpider tests, the A8 starts to shine more.
While the A8 edges out the A7 to be the best performing device and 54% faster than the K1 in SunSpider, the A8 and K1 are neck and neck in the Google Octane benchmark.
Moving back to a graphics heavy benchmark, GFXBench's Manhattan test, the Tegra K1 has a 75% percent performance advantage over the A8 though it is 36% faster than the previous A7 silicon.
These early results are certainly a disappointment compared to the usual generation-to-generation performance increase we see with Apple SoCs.
However, the other aspect to look at is power efficiency. With normal use I have noticed a substantial increase in battery life of my iPhone 6 over the last generation iPhone 5S. While this may be due to a small (about 1 wH) increase in battery capacity, I think more can be credited to this being an overall more efficient device. Certain choices like sticking to a highly optimized Dual Core CPU design and Quad Core GPU, as well as a reduction in process node to 20nm all contribute to increased battery life, while surpassing the performance of the last generation Apple A7.
In that way, the A8 moves the bar forward for Apple and is a solid first attempt at using the 20nm silicon technology at TSMC. There is a strong potential that further refined parts (like the expected A8x for the iPad revisions) Apple will be able to further surpass 28nm silicon in performance and efficiency.