In brief: Apple finally updated its MacBook Pros recently, offering models with 8th generation, 6-core i7 and i9 Intel CPUs. But a YouTuber is suggesting that the 15-inch laptop doesn't provide enough cooling for the latter chip, and that performance is throttled excessively to compensate.
Dave Lee made the claims on his tech-focused YouTube channel. He says the 2.9GHz processor has limited performance due to the MacBook's design, with thermal throttling kicking in quickly.
Lee says an i9-powered MacBook running Adobe Premier Pro showed very serious throttling after just a few seconds, dropping the average clock on load to around 2.2GHz.
"This i9 in this MacBook can't even maintain the base clock speed," Lee said. "Forget about Turbos and all that stuff, it can't even maintain the 2.9GHz base clock, which is absurd. This CPU is an unlocked, over-clockable chip, but all of that CPU potential is wasted inside this chassis, or more the thermal solution that's inside here."
Lee went on to show Premier Pro render times that revealed a 2017 MacBook Pro with an i7 can outperform the new i9 model by four minutes, rendering a clip in 35 minutes. A Windows laptop---Gigabyte's Aero 15X---can do the job in just over 7 minutes, though he does point out that Adobe Premiere isn't as well optimized for MacOS as it is for Windows.
Lee also demonstrated the thermal issues by running the same test in a freezer. It dropped the i9 MacBook's render time down from 40 minutes to 27 minutes, which suggests Apple's thermal solution isn't doing a very good job.
It's worth remembering that the tests were carried out by one person using a single, unoptimized app, so we'll have to wait and see if further examinations show similar results before drawing any solid conclusions.