MacBook Pro Firmware Aims to Fix Thermal Throttling Performance Issues

The latest line of MacBook Pro laptops have been undergoing no small number of issues related to thermal problems, but Apple has been quick to diagnose and issue a firmware fix for the issue. Redesigning the internals may not be on the menu, but solving an issue with a missing vital bit of code for the thermal throttling process does seem to have reduced the issue significantly.

Overheating made the Pro less professional

If you’ve been following the news on the MacBook Pro or have simply noticed performance oddities with a recent Pro purchase, you’re likely familiar with the issue of thermal throttling brought up by YouTuber David Lee in a video that warned about heat negatively impacting performance in the new MacBook Pro line.

Laptops and thermal problems often go hand in hand, but a designer like Apple usually approaches the issue with hardware and software solutions to this problem that allow their aesthetic choices to work alongside the physical restrictions of a laptop. Working professional grade parts into ultra-thin computers isn’t exactly conducive to a cool working environment and most manufacturers are well aware of this shortcoming.

So when the Pro was revealed to have severe throttling issues that led to the inconsistent performance that could dip below that of the 2016 models of Pro laptops. Interestingly enough, taxing the CPU alone caused a different set of issues than taxing the CPU and GPU together, an issue that seemed to point at either a massive hardware problem or a very strange software-level bug.

Thankfully, the issue seems to mostly persist at the software level and Apple hasn’t shipped out a line of laptops that require emergency maintenance. In a release shortly after the initial stories went live, Apple engineers noted the absence of an important digital key in the macOS firmware that negatively impacted how thermal throttling was intended to behave, which led to massive spikes and dips in performance rather than a smooth gradient meant to protect the system while still delivering reasonable results.

Tests run after the update performed by Ars Technica show a distinct improvement in consistency when the CPU is taxed while the GPU is not. Running the GPU and CPU together under load still brings performance down, but it’s nowhere near as dramatic an impact as the worst-case scenario tests from before the update.

It’s difficult to say Apple has wholly negated issues that may be linked to how the Pro’s internals are configured, however, as clock speed results are not promising during GPU-intensive portions of these tests. While a solid 3.5GHz could be reliably obtained as the CPU remained taxed over time, adding GPU taxation to the mix brought core speeds as low as 2GHz. While these numbers are low, it is important to note that they represent a worst-case scenario, yet those core speeds are still slightly worrying for those who intend to play graphically intensive games on a Pro rather than use it as a dedicated workstation.

As always, the Pro exists as a compromise between form factor and performance. If shaving off as much weight and thickness as possible is what you prioritise in a laptop, the thermal throttling issue that previously made it difficult to recommend seems to have been solved and it’s certainly a strong contender for a lightweight and portable option for professionals. If you’re looking for something with stronger performance, especially in graphically intensive applications, you may want to look elsewhere.