With the recent revelation that Apple had (not unexpectedly) sourced the A9 processor in the iPhone 6s from two different suppliers came the discovery that the model manufactured by Samsung is 10% smaller than the one built by TSMC.
Along with the size difference comes a difference in the power efficiency of each model, with many reports indicating—and Apple eventually confirming—that phones with the Samsung chip will likely see 2-3% lower battery life.
Today Ars Technica has published its own findings based on the results of a set of battery tests on each processor, showing that the TSMC hardware outpaces Samsung’s in most test categories, but not all.
For this test, Ars set each iPhone’s display to exactly 200 nits, removed the SIM card from each handset to ensure identical cellular activity, and ran a series of different tests to see how each processor fared.
As you can see in the chart above the TSMC chip has a slight edge in nearly every test, with just one exception: WebGL. In that test, the Samsung A9 actually saw a slight lead over TSMC’s, but for the most part the differences (including Samsung’s lead in the WebGL test) were negligible.
The Wi-Fi browsing test featured the second biggest gap between the two CPUs, and the total difference in that test was only 14 minutes. The GFXBench benchmark showed a 9-minute difference.
The largest gap came from the Geekbench benchmark, which showed a gap of one full hour between the handsets. That outlier aside, the results all line up with Apple’s claim of only 2-3% difference.
With most tests run over the past few days reaffirming Apple’s statement, it seems safe to say that the battery life between the two models is roughly the same, and probably not a big enough difference to cause any great concern. It’s unlikely you’ll see any significant hits to your battery if you happened to get a Samsung unit.