Why Apple’s A16 chip isn’t worthy of its ‘Pro’ name

Every year, Apple ushers in a new A-series system-on-chip to pair with the latest iPhones. This year, the company has taken a completely new path. The new A16 processor is only reserved for the “Pro” model iPhones, while the standard iPhone 14 models get the same A15 we were introduced to last year (the 5-core GPU version found in the iPhone 13 Pro- the models).

The distribution this year and last year is not the only unique thing. The A16 is, more than usual, a relatively small development compared to the previous SoC. There are a few changes to be sure, but the average user will hardly notice them. The differences between the A15 and A16 appear to be relatively mild compared to Apple’s typical annual cadence.

Earlier this year I made some predictions about the A16 that were guided by assumptions that certainly didn’t all pan out. While a few things were true, the performance lift in the A16 is about half of what I predicted, and there are fewer major technological improvements visible. Here’s what’s new in the A16 and what you can expect from Apple’s first “Pro-only” A-series chip.

What has changed from the A15 Bionic

At first blush, the A16 architecturally resembles the A15. There are two high-performance CPU cores and four high-efficiency cores, five GPU cores and 16 Neural Engine cores to run machine learning and AI algorithms. Like the A15.

According to Apple, the chip is manufactured on a new “4 nanometer” process from TSMC, making it the first such processor in a smartphone. However, it’s worth noting that TSMC’s “N4” process is not a 4nm process in the truest sense, and TSMC itself calls it “an improved version of N5 technology.” While it’s a more advanced process than previous A-series processors, it’s not a true next-generation silicon manufacturing process; you’ll have to wait for the 3nm process next year for something like that.

The transistor count has increased a few percent to 16 billion (from 15 billion), and it’s likely that most of the higher budget will be spent on the new display engine (which controls the iPhone 14 Pro’s display down to 1Hz in always-on mode and can crank it up to 2,000 nits in bright sunlight), memory controller and image signal processor.

As for the more general parts of the processor, they seem to have changed almost nothing. The high-performance CPU cores are codenamed “Everest” and can clock up to 3.46GHz, a boost of about 7% over the A15’s 3.24GHz maximum for its “Avalanche” cores. The high-performance cores are codenamed “Sawtooth” and clocked up to 2.02GHz, which is almost the same speed as the 2.01GHz of the A15’s 2.01GHz “Blizzard” cores. Although these cores carry a new name, the architectural changes appear minor at best, as they do not deliver performance beyond the expected increase from the increase in clock speed.

The Neural Engine still has 16 cores, just like in the A15. Apple says it performs up to 17 trillion operations per second, an increase of about 8% compared to the 15.8 trillion A15. I think it’s likely the same design just clocked a little higher.

Perhaps the most significant change is the switch to LPDDR5 memory, which should provide 50 percent more memory bandwidth than the LPDDR4x memory in the A15. Apple actually made the switch to LPDDR5 in the M1 processor line (on the M1 Pro, Max and Ultra), which is based on the A14 chip architecture – the only real surprise here is that the company waited so long to do it in their iPhone-bound chips . There may be some very specific circumstances where a task is completely limited by the memory bandwidth of the A15, in which case the A16 should perform much better.

So at first blush we have what appears to be essentially a higher clocked A15 with a new display engine and perhaps an image signal processor. We have read reports that there are new security measures in the processor’s ROM; not surprising, given how hard Apple works on both the hardware and software sides to make their devices hard to hack.

CPU performance

Given that the CPU architecture hasn’t changed much but just runs at a clock speed up to 7 percent higher (and with more memory bandwidth available), we should expect most CPU benchmarks to show performance gains of 10 percent or less.

A quick look at the Geekbench 5 numbers shows us that the maximum single-core CPU performance actually seems to have increased by around 8-10 percent over the A15. Multi-core performance fares slightly better, but it’s likely that these tests are more easily able to overwhelm the chip’s caches and will therefore benefit somewhat from the increased memory bandwidth.

GPU performance

The A16 Bionic has five GPU cores, just like the higher-end A15 does, and I don’t think there have been any architectural changes. However, high-end 3D graphics tend to be very demanding on memory bandwidth, and I would expect the switch to LPDDR5 memory to have a significant impact here. I don’t have any real insight into the GPU clock speeds, but it would be reasonable to expect the cores to clock around 7 percent higher, like the high-performance CPU cores do.

Taking a look at one of the most demanding 3D graphics benchmarks, 3DMark Wild Life, performance ranges from about 7 percent faster in easy modes to about 19 percent in the “Wild Life Extreme Unlimited” test. That’s a nice improvement, and in line with what I’d expect from a mild increase in clock speed and a big boost in memory bandwidth.

When using the GPU to perform general computations, as tested in GeekBench compute scores (see above), the performance increase is in the 7-8 percent range.

A15+ would be a more honest name

There is no doubt that the A16 is not simply a “binned” version of the A15 (“binning” is when chips tested to perform better in manufacturing are separated and sold as a different model). This is a new chip. But there are no major architectural overhauls here that I can see, just minor revisions to improve maximum clock speed and power efficiency. This is a smaller jump from last year’s model than we’re used to seeing in Apple’s annual iPhone refresh, a fact only emphasized by the fact that the standard iPhone 14 models still use last year’s A15, while still delivers key features like Action Mode, Photonic Engine and 4K Cinematic mode.

Apple didn’t promote any particular feature of the processor as “new” beyond the display engine (which is required to drive the iPhone 14 Pro’s always-on display and 1Hz refresh rate), and in fact marketed it most directly against Android phones and the A13, it’s a three year old flagship. The performance charts just don’t look very impressive with a 7-10 percent performance bump.

To that end, I feel Apple probably shouldn’t have named this chip the A16. In most ways that matter, it’s a tuned A15. Even the new “4nm” manufacturing process is best described as a modified 5nm process. It is probably unreasonable to expect breakthrough advances every year, with brand new architectures delivering 20% ​​performance improvements. The occasional “tune-up” year is fine, especially since Apple has such a big lead in smartphone performance right now. But the naming should reflect that, and a title like A15+ or A15 Pro feels like a more honest representation of this chip.