Apple is having problems with CPU throttling again, but not with iPhones this time around.
The company recently announced a refresh for its MacBook Pro line of devices, which includes an absolutely mind-boggling Intel i9 chip for the 15 inch model.
However, as awesome as the six-core, 2.9 GHz i9-8950HK processor is, the MacBook can hardly utilize it.
The issue, which was first explained by YouTuber David Lee in his video on the MacBook, is with thermal throttling. Throttling kicks in on most computers to reduce CPU speed temporarily when things get too hot. However, with the MacBook Pro 2018, the issue is much worse.
The aluminum chassis that give the MacBook its iconic, sleek look is a double-edged sword. In this case, the sleek look sacrifices airflow, meaning things get much hotter on the inside. With the i9 version, this is more pronounced.
Lee reveals in his video that after a few seconds of high-intensity work — in this case, Lee uses Adobe Premiere to render video — the MacBook begins throttling.
According to Lee, the device’s average clock speed under load is 2.2 GHz.
“This i9 in the MacBook can’t even maintain the base clock speed,” says Lee.
How the 2018 MacBook stacks up
To show the extent of the issue, Lee ran his test with the MacBook inside a freezer. This actually lowered the render time. Outside the freezer, it took nearly 40 minutes to render. In the freezer, the render time drops to 27 minutes.
Lee also runs the test on a 2017 MacBook Pro, which took about 35 minutes. Furthermore, he tested a Windows laptop, the Aero 15X, which sports a slower i7-8750H, with a base clock of 2.2 GHz, which completed the render in seven minutes.
It’s important to note that Premiere Pro, as Lee says in his video, is better optimized for Windows than Mac OS. However, that alone isn’t enough to account for the difference in render times. The i7 in the Aero 15X maintains an average clock of 3.1 GHz throughout the test, significantly higher than what the 2018 MacBook Pro.
While thermal throttling isn’t a new phenomenon, it does affect both Windows and Mac platforms. However, the issue Lee has with the MacBook is the degree of thermal throttling on display.
Granted, this is a single test with a single app — optimized apps may perform better. It also could be an isolated issue.
Either way, it may be safer to hold off on the i9 model for the time being.