iPhone 17 Pro's Alleged Vapor Chamber Cooling System Partly Revealed

[Andy_2341]

It was sunny and 28C or 82F

Yeah, I’d say that’s a hot day.

 

[ultratiem]

They say they have improved the cooling with every generation since the iPhone 13, but it’s still the same problem because the performance gains of the chip offset the improvements in cooling.

Hello hamster. I’d like you to meet my friend, wheel!

 

[fzJNotIBOxgnbqejSeVCvJScL]

A lot of the thermal problems can be mitigated when we switch from 3nm to 2nm, an unprecedented 33% size reduction.

Same for the Android phones.

On the Apple side, the second or third generation of the in-house 'C' modem chip can also help with battery life and thermals.

Over to you TSMC, please ramp up those yield numbers in 2026.

 

[emrelee]

I’ve been using my phone in a similar manner since the iPhone was released. I engage in conversations, share images and posts, watch videos, and occasionally use the maps. However, every year, Apple releases new iPhones that are larger and heavier, featuring improved chips and batteries. Despite these enhancements, my battery life remains the same, and I find it difficult to hold the phone in my hand due to its excessive heat. From a user’s perspective, my experience with the phone remains unchanged, and all they seem to do is release updates to apps, which eventually lead to a significant slowdown in the phone’s performance, even for tasks that have remained consistent for the past decade.

 

[subjonas]

They say they have improved the cooling with every generation since the iPhone 13, but it’s still the same problem because the performance gains of the chip offset the improvements in cooling.

This sounds about right. I think it's similar to battery life how thy keep it relatively consistent. Apple will often make power consumption more efficient but may offset it with a thinner phone (and smaller battery), or they’ll offset a bigger battery (and thicker phone) with more powerful processing, so that battery life stays roughly the same no matter what, or at least changes very incrementally. I think Apple chooses to keep certain aspects of UX--like battery life and how hot to the touch a phone casing can get under heavy load--as somewhat constants, and try to improve other aspects of each new generation of iPhone, like chip power, phone thinness, and heat dissipation.

 

[subjonas]

What are y’all doing with your iPhones to make them get hot so easily? My SE3 overheated 1 time after being left in direct sunlight for several hours in a black case. My 15 Pro has never overheated and I take advantage of full brightness in direct sunlight often as well as game at max settings connected to an external 4k monitor.

Of course, I’m still excited for the vapor chamber.

I think my SE3 might have overheated in direct sunlight a couple times, not sure. But it would almost always overheat when using CarPlay (not in direct sunlight). Not sure if it was because it was wireless.

 

[subjonas]

Wow, why didn’t they think of that? Somebody get this to Tim immediately

OP was pointing this out to people here who don’t realize this, because it’s not obvious to everyone. Some people here seem to think better heat dissipation will make everything better. But they don’t realize that while it will make the phone run better, unless Apple has some other trick up their sleeve it will also make the phone casing feel hotter to the touch since that’s how the phone gets rid of its heat. So the only way for the phone to run well without overheating AND to not feel hotter to the touch is to make the chip and/or software more power efficient (again unless Apple has some other trick up their sleeve).

In other words, this:

People, better cooling means the whole phone get hotter because the heat is spread from chips to the body. It will not make the phone cooler but will help with sustain performance. If you want the phone to be cooler then it should produce less heat in the first place. Meaning limit peak performance, more efficient software and hardware.

 

[unphased]

it will also make the phone casing feel hotter to the touch

This would be mildly more of a feature. I'd like to have a more immediate realtime feedback on processing load via the sense of temperature because i dont use my phone as a primary computing device, it is a secondary computing device. it needs to do its processing and then finish and keep its battery reserve for processing later on in the day! With no readily available ActivityMonitor.app on iOS i might as well employ this very intuitive sensory mode to instantly know how quickly my battery is being drained at any time.

if it is more efficient at bringing the heat out to the surface from the internal chip it will give the internal chip more thermal headroom and it will increase the efficiency with which i can sense how much power it's pulling, which could be pretty cool.

Another thing is for some inexplicable reason they don't give us a way to tell it to lock the phone if we pocket it without locking it (the damn thing has a proximity sensor...) so if it heats up more efficiently then i'm gonna be able to detect this condition more quickly, which is better for battery life since the more time that battery spends hot the more it degrades, and I'd like to keep that degradation to only happen when i cannot avoid it like recording something on a hot day under direct sunlight rather than letting it waste away on its own with the camera app open furiously struggling to focus on the inside of my pocket ad infinitum.

All that having been said: At some point the surface getting too hot will be an issue. case in point i have done a thermal paste mod on my 12" macbook and it throttles less and is a more usable computer as a result, but it's now indeed uncomfortably hot on its bottom whenever it's doing... anything at all... I still love that little computer but it's too damn slow with the macos bloat nowadays. But i can't just throw linux on it and lose sleep and wifi, so it's really kind of sad.