Apple | MacBook Pro: How supply bottlenecks led to changed M2 design and more heat | News | macbook

The MacBook Pro 14″ or 16″ that has just been updated brings the M2 chip with it as the most important innovation. Although there are improvements in other areas, such as HDMI 2.1, the use of the M2 is still considered the most important step. As iFixit already noted in the disassembly report, the inside of the MacBook Pro 2023 looks almost the same as the MacBook Pro 2021. However, two important changes were noticeable – on the one hand the memory configuration in the base model (2 instead of 4 modules), on the other hand a changed cooling system. According to initial tests, the M2 devices get a fair bit warmer than their M1 ancestors and also heat up faster – this is not only ensured by the additional cores, but probably also by the smaller heat sink.

Lack of material leads to chip changes
It is interesting why Apple shrank the chip cooling. According to the analysis, this is due to a modified design of the M2 SoC, which in turn is due to delivery problems. Like it Vadim Yuryev summarized by MaxTech, the so-called ABF substrates for manufacturing the carriers between chips and printed circuit boards are one of the main reasons why chip bottlenecks occur in the first place. There is an acute shortage, which is why Apple adapted the design of the M2 to use as little material as possible. While an M1 uses two large chips for shared CPU and GPU memory, an M2 uses four small modules.

More memory bandwidth, less cooling
That may also explain why memory bandwidth doubled, with the MacBook Pro’s M2 Max at 400 GB/s beating the 200 GB/s of the 2021 M1. The downsized cooling system adapts to the chip changeovers. According to Yuryev, a larger heatsink wouldn’t make sense because otherwise the lower part would just cover parts of the board that don’t need cooling. At the same time, the advantage of a faster memory connection is offset by the aforementioned weaker cooling of the chip, because more heat is generated on a smaller area.

Reason for postponement of the Mac Pro?
One assumption is that the delays in the Mac Pro and the allegedly canceled plans for an M2 Extreme are due to the lack of substrate described. An M2 Ultra already needs twice as much material as an M2 Max – and an M2 Extreme even four times as much. If Apple is already making such changes to the M2 Pro/Max of the MacBook Pro, the concern is probably not being able to obtain even more powerful chips in sufficient quantities.