iPhone 15 OverheatGate Seems to Be a Nothingburger

Sunday, 1 October 2023

On Tuesday, Ming-Chi Kuo published a short post under the headline “The iPhone 15 Pro Series Overheating Issues Are Unrelated to TSMC’s Advanced 3nm Node”:

My survey indicates that the iPhone 15 Pro series overheating issues are unrelated to TSMC’s advanced 3nm node. The primary cause is more likely the compromises made in the thermal system design to achieve a lighter weight, such as the reduced heat dissipation area and the use of a titanium frame, which negatively impacts thermal efficiency. It’s expected that Apple will address this through software updates, but improvements may be limited unless Apple lowers processor performance. If Apple does not properly address this issue, it could negatively impact shipments over the product life cycle of the iPhone 15 Pro series.

That was the whole post. The post clearly implies that iPhone 15 Pro models have a design flaw related to their titanium frame that leads to overheating, and that since the flaw is related to the hardware design, Apple will be forced to throttle the CPU and GPU, and thus sales of the 15 Pro models will suffer.

Kuo is very influential, and thus his report drove Apple’s stock price down noticeably. Kuo’s influence stems not from his intuition but from his sources, but that’s the problem with an allegation like this one. Kuo’s narrative gained enough traction that Apple has issued a statement, repeated in its entirety below:

We have identified a few conditions which can cause iPhone to run warmer than expected. The device may feel warmer during the first few days after setting up or restoring the device because of increased background activity. We have also found a bug in iOS 17 that is impacting some users and will be addressed in a software update. Another issue involves some recent updates to third-party apps that are causing them to overload the system. We’re working with these app developers on fixes that are in the process of rolling out.

Not only is the titanium frame of the iPhone 15 Pro models not an issue, cooling-wise, but Apple told me — and I have no reason to doubt — that the iPhone 15 Pro and Pro Max are better at heat dissipation than any previous iPhone that used a stainless steel frame (iPhone X, XS, and 11–14 Pro). There is absolutely nothing wrong — and in fact much that is good — with the heat dissipation of the titanium frame, and Apple has no plan to in any way throttle the A17’s performance. They have bugs to fix in iOS 17, that is all.

It’s long been true that iPhones sometimes get warm/hot during the first few days after setup (or complete restore): all sorts of large libraries (like Photos) get synced in the background, and all sorts of on-device processing takes place. There are also often performance-related bugs in the first release of the major new iOS version each fall — and per Apple’s statement, this year is no exception.

As for the problematic third-party apps, one of them is Instagram, which has apparently just this week released a version fixing a bug that was so egregious that it was burning through iPhones’ battery life at a rate of 1 percent/minute just sitting idle. YouTuber Faruk “iPhonedo” Korkmaz posted a video this week showing the buggy version of Instagram heating two different iPhones to 100°F: one an iPhone 15 Pro, the other a year-old iPhone 14 Pro. Exact same overheating issue. (I question here why iOS allows any app to consume so many resources that it makes the device too hot to hold comfortably, but the bug was apparently Instagram’s. Same too with Uber. Real shocker that two apps made with a Frankensteinian mishmash of web and native UI toolkits would run amok, resource-wise.)

Ming-Chi Kuo obviously has some remarkable sources within Apple’s Asian supply chain. But he’s still sometimes very wrong. And — unlike Mark Gurman — Kuo’s sources seemingly never come from within Apple itself. His post on this overheating issue is almost transparently a leak from TSMC — a sort of “Whatever is going on with the iPhone 15 Pro heat dissipation, it has nothing to do with our 3nm process”. Blaming it on the new titanium frame was just wild speculation on Kuo’s part, and by all evidence is completely wrong.

If Kuo has any respect for accuracy or truth, as I’m sure he does, he’ll issue a full retraction.