We made the iPhone 17, 17 Pro and Air sweat: which one really heats up the most?

We talk more often about power than temperature. However, with their ever more muscular chips, smartphones have become real heaters as soon as we titillate them a little too much. To find out, we submitted the three new Apple terminals to the benchmark Solar Bay Extreme Stress Test Unlimited Mode, in other words the ultimate punishment from 3DMark. A graphics marathon that pushes devices to their limits.

We have them in turn fixed vertically, bare backs facing our thermal camera, without shell, without accessories, without excuses. The objective was to measure three crucial points that Apple’s keynote never clearly displays: the time before heating (when the 40°C mark is reached), the maximum temperature and the ability to cool down, in other words the time it takes for these iPhones to return to 35°C. In theory, the iPhone 17 Pro and its vapor chamber should dominate. Let’s move on to practice.

Three iPhones, three strategies

Apple can release three models of the same generation, but they are not in the same boat. L’iPhone 17 standard plays the card of continuity compared to its predecessors. The 17 Pro benefits from THE novelty of 2025 borrowed from the competition, namely a chassis unibody in aluminum associated with a vapor chamber and the A19 Pro chip, when the iPhone 17 is content with a classic version of this in-house processor.

And then there is theiPhone Airthe one who puts the slimming diet above all else. Thinner, lighter… and inevitably less well ventilated. Here, the key word is aesthetics. But when it comes to feverishness, finesse is always punished. No steam chamber here, but the same chipset than the iPhone 17 Pro in a slightly redesigned version.

Grilling

From the launch of the benchbehaviors differentiate quickly. The iPhone 17 gets the ball rolling with the start of heating at 3 min 35 sec. The temperature rises, but is concentrated above all at the top right of the chassis, opposite the photo modules. The peak still reached 47.6°C, well above “tactile comfort”, before returning to 35°C after 5 min 27 s. Hot, yes, but predictable.

Quiet strength isiPhone 17 Pro. It takes 7 min 49 s to cross 40°C – an eternity at this intensity. The heating is diffused, less unpleasant and more harmonious. The peak remains contained at 44.8°C and the cooling, although stable, takes its time with 7 min 30 s to fall back to 35°C. Slower, but also more constant, it is the only one that never gives the impression of imitating Icarus.

And then comes the iPhone Air which quickly builds pressure, barely 40 seconds to exceed 40°C. Instantly, the heating is installed in the center in alignment with the photo sensor, then spreads over the entire upper part. Finesse shows its limit here: there is no room to dissipate calories. THE frame rate falls, like a survival reflex, but the temperature rises to 48.3°C, the highest peak of the trio. It then comes back down in 4 min 53 s, but the tactile impact remains memorable.

Enough to cool the ardor

If the iPhone 17 knows how to remain reasonable, its Pro version is the only one to really seem designed for stress. The iPhone 17 Pro never panics, keeps a cool head longer than all the others and confirms an essential point: yes, Apple finally knows how to cool a high-end iPhone.

As for the iPhone Air, its extreme thinness comes at a price. This is clearly not a terminal designed to run Genshin Impact to its maximum. Unless you’re willing to sacrifice one of your hands on the grill by holding the unit horizontally. We say that, we say nothing…