The S8 chip in the Apple Watch Series 8, Apple Watch Ultra and second-generation Apple Watch SE has the same CPU as the S6 and S7 chips, according to the identifier. the CPU inside Apple’s S8 SiP is the same as the CPU in the S6 and S7 chips that debuted in the Apple Watch Series 6 and Apple Watch Series 7. The CPUs in the S6 and S7 chips that debuted in the Apple Watch Series 6 and Apple Watch Series 7 carry the same T8301 identifier, which explains why Apple has only compared its S-series chips to the S5 chip or earlier in recent years.
This also means that Apple Watch Series 6, Apple Watch Series 7, Apple Watch Series 8, Apple Watch Ultra and the second-generation Apple Watch SE all use the exact same CPU. notably, Apple may still have iterated on other parts of the SiP to accommodate new components, such as the Apple Watch Series 8’s new accelerometer and gyroscope.
The S6, S7 and S8 chips all feature 32GB of storage and dual-core CPUs. when Apple debuted the S6 in Apple Watch Series 6, the last time it made performance claims for its latest smartwatch line, it said the chip allowed apps to launch up to 20 percent faster.
The S6, S7 and S8 are based on Apple’s A13 Bionic chip for the iPhone 11 series, manufactured using TSMC’s 7nm process. Apple began its transition to TSMC’s 5nm process with the A14 Bionic chip, and the iPhone 14 Pro’s A16 Bionic chip was the first Apple chip to be made on a 4nm process.
One explanation for Apple not advancing CPU technology for its S-series chips is that the advances made using the cores in the A14 chip and TSMC’s 5nm or 4nm process will primarily yield performance improvements that are no longer important for Apple Watch usage. On the other hand, waiting for TSMC’s 3nm process, which will enter mass production by the end of this year, could yield more meaningful efficiency improvements – a more important area when it comes to the Apple Watch, as it could help extend battery life.
