How the iPhone’s A18 Pro chip will supercharge Apple’s AI revolution

Macworld

When the iPhone 16 line launches this September, we expect it to usher in a new A-series processor. As has been the case in the last few years, the top-end “Pro” models will get a new processor while the regular iPhone 16 non-Pro models will likely get a version of the A17 Pro chip found in this year’s iPhone 15 Pro.

As we do every year, we’ll look at the history and performance of the A-series processors from the last several years, along with the recent rumors and overall industry trends, to anticipate what we might expect from Apple’s new iPhone silicon this fall. As always, this is all just guesswork; Apple is a famously secretive company, and the details about its products are often not fully revealed until they are released.

To “Pro” or not to “Pro”?

Last year, Apple introduced what might be an all-new wrinkle into the expected upgrade pattern. Changing the name from “A17 Bionic” to “A17 Pro” for the first time, the implication is that there would be a new non-Pro chip each generation too. That hasn’t yet come to pass, but we might see something different this year.

There are three likely possibilities for what Apple may do in addition to making a new A18 Pro for the iPhone 16 Pro and Pro Max:

  • Make a new A18 for the regular iPhone 16 and 16 Plus that is essentially the A17 Pro given a new name. There might be minor technical differences but performance and features would be the same as the A17 Pro.
  • Apple makes a newly-designed A18 chip for the non-Pro iPhones. It’s based on the same architecture as the A18 Pro but with lesser performance in some areas (perhaps due to lower clock speed or reduced active core count).
  • Apple keeps using the A17 Pro for the iPhone 16 and 16 Plus; the A18 Pro is the only “new” iPhone chip this year. This is what Apple did in the iPhone 14 and iPhone 15 generations.

It’s hard to say which is more likely, only that the high-end chip will probably once again carry the “Pro” name instead of “Bionic” and launch only in the iPhone 16 Pro models. We’ve heard rumors that the lower-end chip in the iPhone 16 will be called “A18” this year, but even if that’s true we don’t know if it will be an truly new chip or just a rebranded iPhone 17 Pro. And we heard similar rumors last year that didn’t pan out.

Our analysis here is targeted at the A18 Pro, what we assume Apple will call the higher-end version of the chip powering this year’s iPhones.

Still made with a 3nm process

The A17 Pro was the first mass-market consumer chip to use a 3nm manufacturing process. And while TSMC is on track with the 2nm chips that come next, we don’t expect to see an Apple product using that process until next year a the earliest. So the A18 Pro will be made with TSMC’s 3nm process again.

The 3nm process used for the A17 Pro was known as N3, and as the first iteration of 3nm technology from TSMC it was pretty expensive. The company has a newer process known as N3E, which is far easier to manufacture at scale. It should be slightly more power efficient than the original N3 process but also slightly less “dense”, which means a chip built using N3E would be slightly larger than an identical chip made with N3.

There are rumors that the A18 Pro will be a physically larger chip than the A17 Pro—the switch to N3E may be one reason, but we expect Apple will also increase transistor count to more then 20 billion (A17 Pro is a 19 billion transistor chip). To put that in perspective, a modern Intel “Raptor Lake” generation laptop CPU is estimated to have a transistor count around 26 billion transistors, which the top-tier large Nvidia GeForce 4090 RTX desktop GPU is a 74 billion transistor chip.

CPU performance will probably improve

All the rumors have focused on AI performance, and why not when that’s the hot topic of the day? But Apple is always concerned about CPU performance, and shares core designs between its A-series iPhone/iPad chips and it’s M-series Mac (and iPad Pro) chips.

Just look at this chart of single-core Geekbench 6 performance for iPhone chips all the way back to the A11.

Foundry

What strikes me as most remarkable is just how steadily single-core performance has increased. We’ve estimated the A18 performance by continuing the trend from the last several chips, and it gives us a single-core Geekbench 6 score of almost 3,200. That’s just a touch faster than an Intel Core i9-13900KS, a very high-end desktop CPU.

Of course, powerful desktop and laptop CPUs have many more cores than a phone processor. We think the A18 Pro will have the same core configuration as most recent A-series chips: two performance cores and four efficiency cores.

Foundry

Faster cores, cache, and memory will push up the multi-core score even if Apple uses the same number of cores. We’ve seen a pretty steady performance trend for multi-core performance as well, and don’t expect that to suddenly change. A multi-core score of over 8,200 would put the A18 Pro in the same territory as a mid-tier Intel or AMD laptop CPU from about three years ago.

GPU performance always goes up

Using the modern 3DMark Wild Life benchmark in Unlimited mode, we get a good idea of how much GPU performance has improved over time. Frame rates have more than quadrupled since the iPhone X days. It’s not quite as steady as CPU performance–some years the uplift is 10 percent or less and in others years it’s closer to 30 percent.

Foundry

We don’t have any reason to believe that GPU performance won’t be better this time around as well, though the rumors say Apple isn’t adding more GPU cores. Architectural efficiencies can go a long way. Our guess is a 10-15 percent improvement in real-world CPU performance.

The 3DMark Solar Bay test stresses ray tracing performance, so you see much lower frame rates overall.

Foundry

Performance took a huge jump up with the A17 Pro in this test because Apple added hardware to help accelerate ray tracing. There may be some tweaks this year, but we don’t think a similar jump can be expected in this test in the A18 Pro–again, we’re probably going to see a 10-15 percent boost.

Neural Engine may get a big upgrade

The Neural Engine is Apple’s name for it’s NPU or “Neural Processor Unit”—specialized hardware made to optimally run neural networks for machine learning, deep learning, and AI software in the same way the GPU is made for graphics processing.

Apple is said to be all-in on AI this year, with big AI features coming to iOS 18 and the iPhone 16 line. I think that means we can expect a big improvement in Neural Engine performance.

But the Neural Engine has been getting faster at a regular pace since it was first introduced in the A11 (found in the iPhone 8 and iPhone X). That first Neural Engine could perform 600 billion operations per second, while the Neural Engine in the A17 Pro is touted as able to handle 35 trillion operations per second (TOPS).

Here’s how that performance increase over time has manifested in performance using the new GeekBench ML benchmark, targeting the NPU only.

Foundry

Geekbench ML is a relatively new benchmark, only on version 0.6, that runs a suite of machine learning tasks like image recognition, object classification, image super resolution, and language processing to assess the performance of CPUs, GPUs, and NPUs. When running the test only the the Neural Engine, we see a more than 8-fold improvement over the last six years, and an average yearly speedup of roughly 20%.

Notably, the score did not double from the A16 to A17 generation even though Apple said Neural Engine performance jumped from 17 TOPS to 35 TOPS. The claimed maximum performance specs often don’t match real-world performance numbers.

Apple’s Neural Engine already delivers much better performance than competitors like the NPU in the Snapdragon 8+ gen 1 (around 2,800 points depending on which phone it’s in) or Google’s Tensor G3 (under 2,400 points). Simply taking the past performance gains and projecting it forward would give us a score of almost 4,100 points and a commanding lead over most competitors.

I think we can safely ignore this chart for the A18 Pro, however. Recent rumors suggest that Apple will dedicate more silicon to the Neural Engine and push for a big performance boost in order to power more advanced AI features entirely on-device. I wouldn’t be surprised if Apple touted a really big number for its Neural Engine this year–over 50 TOPS is almost certain—and we could see a Geekbench ML score closer to 5,000.

RAM, 5G, and more

Of course, there’s more to the A18 Pro than the CPU, GPU, and Neural Engine. Then there are related chips that aren’t technically part of the A18 Pro but are still important to iPhone users, like the cellular modem.

The new LPDDR6 memory standard is still too new to make it into this year’s iPhones, but Apple could move from LPDDR5 to LPDDR5x—providing for slightly more memory bandwidth and while using less power. The A17 Pro made the leap from 6GB to 8GB of RAM and it feels too soon for Apple to jump up again. On the other hand, AI models tend to be very memory-intensive and we could see Apple increase RAM just to enable bigger and more sophisticated AI models on the new phones.

On the wireless front, we should expect an upgrade to Qualcomm’s Snapdragon X75 modem for faster and more reliable 5G connections. Apple has been working on its own wireless chips for years but is having a hard time getting them to a point where they provide a good enough experience. There have also been rumors of an upgrade to Wi-Fi 7, and of course, we can expect Ultra Wideband, Bluetooth, and NFC features that are similar to those in the iPhone 15 line.

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