The new MacBook Air gets so hot it affects performance. It is not the first time [Updated]
Update: Based on iFixit’s teardown, a previous version of this article claimed that the MacBook Air M2 did not include any type of passive cooling for the M2 chip. Several Ars commenters have pointed out that this is probably incorrect – the thermal paste seems to bridge the gap between the M2 and the strip of metal above it, and this strip of metal is likely to serve as some sort of heat sink (plus RF shielding that helps prevent wireless interference).
It remains true that the temperature peaks of the M2 chip in both the MacBook Pro and MacBook Air may exceed maximum M1 chip temperatures during sustained workloads, including heavy photo and video export jobs. The M2 Air’s thermal throttling can sometimes slow it down enough to make it no faster than the M1 Air it replaces, although this is something many users will never encounter in day-to-day use.
It also remains true that adding more thermal pads to any Apple heat sink has included, that the performance of the M2 Air can be measurably improved while reducing its maximum operating temperatures. That’s something to consider when choosing between the Air, the M2 Pro, or the larger MacBook Pros with M1 Pro and M1 Max chips and active cooling systems.
Original story: If you read iFixit’s teardowns, in-depth reviews, or follow any tech YouTuber, you might have read that the recently redesigned MacBook Air’s M2 chip is having heat issues.
Although not all MacBook Air owners notice, we did notice in our MacBook Air review that the MacBook Pro M2 could be up to 30% faster than the same MacBook Air M2. More adventurous YouTubers went further: the Max Tech Channel installed thin thermal pads on the MacBook Air M2 that dramatically improved the chip’s performance in real and synthetic benchmark tests, while lowering the maximum temperature by the chip from 108° Celsius to a less toasty 97° Celsius.
Before we continue, this mod is not something we condone. Besides voiding your new MacBook Air’s warranty, adding thermal pads that conduct heat from the M2 to the bottom of the laptop could lead to all sorts of unintended consequences, including but not limited to: “make your knees really warm”. You also risk accidentally damaging the M2 or other components. Seriously, don’t mod your new MacBook Air just because some YouTuber did (or at least give others more time to find out any unforeseen side effects so you don’t have to).
Thermal pads, heatsinks, and heatsinks all work the same way: they make close contact with the processor and draw heat away from it. As this heat is spread over a larger area, it becomes easier to dissipate, which aids in CPU cooling. MacBook Airs include passive (i.e., fanless) heat sinks that draw heat away from the chip, while MacBook Pro M1 and M2 use active cooling systems that draw in cool air and eject hot air for even more efficient cooling.
But it seems that the passive heat sink of the M2 version of the Air is having a harder time than that of the M1 version of the Air. Due to the higher temperatures, the M2 must throttle more aggressively to avoid overheating. Especially for people who edit and export high resolution photos and videos, this means the M2 in the Air may struggle to run faster than the M1 it replaces.
This isn’t the first time a MacBook Air has had noticeable thermal throttling issues – the 2020 Intel MacBook Air was also capable of much better performance than it offered, and the culprit was also the cooling system.
In a real world situation of do what I say and don’t do what I do, I modified my 2020 Intel MacBook Air, so that I could speak with more authority about its heat issues. The problem wasn’t that Apple didn’t include a heatsink and fan, but that the heatsink was misconfigured – there was too big a gap between the bottom of the heatsink and the top of the processor, and Apple had to use a bigger glob of thermal paste to fill that gap. But where a thin a layer of thermal paste can fill tiny gaps and also improve conductivity and heat transfer a lot thermal paste leads to much less efficient heat transfer. Oops! Possible solutions to the problem include using thin copper shims to fill the gap between the CPU and heatsink, as well as placing a thermal pad on top of the Air heatsink to improve conductivity .
Even though the causes of the thermal problems of these two MacBook Airs are different, the two problems are certainly feel avoidable. Maybe Apple is trying to save money or make the MacBook Air a bit lighter. Maybe the company thinks the performance degradation won’t be noticeable to most people most of the time (which is probably true). Perhaps the company doesn’t think most people will be using their MacBook Air for sustained workloads that force the processor to reach its thermal limits (although that’s an odd assumption to make, given the surge in company’s interest in gaming in macOS Ventura and the MacBook Air (position of Apple’s most popular laptop).
Whatever Apple’s reasoning, leaving the M2 running at higher temperatures for many years could eventually become a reliability issue: the hotter the computer’s components are, the faster they wear out. It’s also the MacBook Air design we’ll likely be living with for the next three to five years, going through the previous one. Apple should cool everything of these systems correctly, for the good of the material and the people who use it.