After Chipworks confirmed last week that Apple’s latest iPhone 6S and 6S Plus use A9 chips supplied by both TSMC and Samsung, customers went crazy testing the performance of each variant. Early benchmarking tests showed that the performances of iPhone 6S units running Samsung- and TSMC-made A9 processors were almost identical. But certain battery life tests showed there was as much as 20% different in battery longevity between the TSMC and Samsung processors, in favor of TSMC.

iPhone 6S With TSMC-Made A9 Chip Offers Slightly Better Battery Life

The actual difference is no more than 2% to 3%

Apple quickly shot down those reports by issuing an official statement that these tests painted an “unrealistic” picture of the real-world iPhone 6S battery life. The tech giant added that the difference in battery life between iPhone 6S variants with any combination of components was no more than 2% to 3%. Now Ars Technica has released results of tests conducted using two iPhone 6S models, one powered by Samsung-made A9 chip and another running TSMC processor. And results are in line with Apple’s statement.

iPhone 6S Battery Life

TSMC’s processor performed slightly better than Samsung chip in GFXBench and WiFi browsing tests. Ars Technica used two AT&T iPhones with their SIM cards removed. Each iPhone 6S test unit was set to the same display brightness. However, the TSMC variant outperformed the Samsung model by a whopping 28% in Geekbench 3. Apple says Geekbench tests are unrealistic because they force a device to operate at peak CPU usage until its battery dies.

iPhone 6S users need not worry

It means the iPhone 6S powered by Samsung-made A9 might prove detrimental only under extremely CPU-intensive tasks. The Samsung chip outperformed its TSMC counterpart in WebGL test. Ars Technica’s test results are in line with other tests conducted by Reddit users and Apple fans. The publication concludes that there are certain circumstances where TSMC chip edges out the Samsung one, but the difference is very small. So, users of iPhone 6S with Samsung chip inside shouldn’t worry about the battery life of their phones.

TSMC uses 16nm FinFET technology to manufacture A9 chips while Samsung relies on 14nm technique. The two companies, along with Intel, have also reportedly won the contract to supply A10 chips for the next year’s iPhone 7.