No, Apple is not throttling its A-series chips for easy upgrades later

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2020 iPad Pro builds on the 2018 model.
The 2020 iPad Pro offers an additional GPU core, but its chip hasn't changed.
Photo: Ed Hardy/Cult of Mac

A new investigation into Apple’s improved A12Z Bionic chip inside the 2020 iPad Pro reveals that it features exactly the same GPU found in the A12X Bionic for 2018 iPad Pro units. The one big difference is that an additional eighth core is now enabled, making it slightly faster.

Many fans are now criticizing Apple for what seems, at first glance, as intentional throttling. It is assumed Cupertino is disabling features in its newest chips, only to enable them later and market them as improved — even though they’re essentially the same on the inside.

Could it be that this is a scheme to make quick and easy cash? Actually, no. This is standard practice across the semiconductor industry. Others like Intel and Nvidia use exactly the same approach — and there’s a very good reason for it.

Here’s the real reason why an A12Z is just an A12X with unlocked potential.

Apple has received heaps of praise for its A-series chips since the very first — the A4 — debuted inside the iPhone 4 in 2010. For nearly ten years now, those chips have been outperforming rivals from the likes of Snapdragon, and even giving notebook processors a run for their money.

That’s despite the fact that Apple’s chips typically run at slower clock speeds, and with fewer cores than their competitors. The company’s chip designers have mastered the art of building incredibly efficient CPUs and GPUs, and squeezing every bit of power out of them.

Apple’s amazing A-series chips

For instance, the A12X Bionic from 2018 can outperform not only other tablet chips with ease, but also many notebooks. And we’re not just talking about cheap Windows laptops with budget CPUs here; the A12X makes the iPad Pro faster than some MacBook Pro models.

It turns out, however, that it could have been even faster — at least in terms of graphics processing. In digging into the A12Z Bionic, Notebook Check discovered Apple’s newest chip is actually identical to its predecessor on the inside. Its internal makeup has not changed.

Instead of designing a new chip, Apple simply enabled an eighth GPU core that was already there, but previously disabled. At first this seems shady, like Apple intentionally throttled the A12X with a plan to unlock its full potential later for an easy, low-cost upgrade.

In reality, that’s almost certainly not the case.

Chip manufacturing is hard

What you might not know is that the chipset manufacturing process is incredibly difficult. It requires countless different steps, and even when those are carried out perfectly, the chances of things going wrong — and for some chips to turn out defective — is surprisingly high.

This is true even for the most experienced chip manufacturers. For example, an April 2019 report from Bits and Chips revealed that AMD, one of the biggest names in the business, was seeing yield rates of around 70% for its 7-nanometer Zen 2 CPUs at the time.

In other words, for every 100 Zen 2 processors AMD manufactured, only 70 of them were usable. That’s a pretty decent rate (believe it or not) for what was a brand-new architecture for AMD a year ago. Yield rates for more advanced chips can be significantly lower than that.

With Intel’s high-end Xeon CPUs with 28 processing cores, for example, it is believed the yield rate is less than 40%. That’s one of the reasons why those that do turn out perfectly are so expensive. The yield rates for more common Intel CPUs is rumored to be around 60%.

Not all bad chips are bad

The “bad” chips that don’t turn out right don’t always go straight into the trash. Where possible, manufacturers will sensibly repurpose those chips and bring them to market as more affordable products with different branding. This is common for both CPUs and GPUs.

If you go out today and buy an Nvidia RTX 2060 KO graphics card, which retails for around $329, you’re likely getting an RTX 2080, which retails for around $699, that didn’t turn out quite right. It’s still perfectly usable, it’s just not as beefy as it was designed to be.

When you buy a computer powered by a dual-core Intel Core i3 processor, you end up with a chip that was originally intended to be a quad-core Core i5. It didn’t meet Intel’s specifications, but rather than being scrapped, two of its cores were disabled and it was repurposed.

The process of repurposing and recategorizing chips is known in the industry as “re-binning.” And it’s likely what happened in 2019 with Apple’s brilliant A12X Bionic chipset … but not quite.

A12X vs. A12Z

There will be some differences between the way Apple and others design their chips. Unlike AMD, Intel, and Nvidia, Apple doesn’t offer a wide variety of different chips at different price points. There’s typically only two per year — one for iPhone, one for iPad.

It’s sensible to assume, then, that rather than re-binning chips that don’t meet specifications, Apple designs its own with room for error so that a greater number of them can be used. It’s possible the A12X was always intended to feature a seven-core GPU, but an additional core was added in the knowledge that not all would turn out perfectly.

Why, then, was Apple able to enable that eighth GPU core for the A12Z in its newest iPad Pro? Well, over time, manufacturing processes improve and fewer errors occur. The kinks are ironed out, and yield rates increase. It seems Apple has gotten to that point with the A12Z.

So, it is now cost-effective (whereas it wasn’t before) to market the A12Z’s full potential and start shipping those chips completely unlocked.

Why hasn’t Apple done this before?

What’s surprising about all of this isn’t that the A12Z is essentially an unlocked A12X. It’s that this is the first time — that we know of, at least — Apple has taken this approach with one of its A-series chipsets, even though it’s such a common practice.

It is believed that Apple’s chip manufacturing partner, Taiwan Semiconductor Manufacturing Company, can deliver impressive yield rates. Rumors claim that those for the upcoming A14, which should debut in this year’s iPhone lineup, are exceeding 80%.

It may be that Apple simply hasn’t seen a need for this approach in the past, then, but we certainly wouldn’t be surprised to see it used again in the future. It doesn’t mean that Apple is scamming us with throttled CPUs just so that it can sell them to us twice.

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