Apple’s new M4 Pro chips, found in both the Mac mini and the 16-inch MacBook Pro, deliver impressive performance. However, my testing revealed a surprising change in the way they operate, particularly in their Low Power mode. This change, which Apple has extended to the “Pro” level chips for the first time, is a significant departure from previous generations.
Let’s break down the new power modes: Low Power, Automatic, and High Power. The most noticeable shift is in Low Power mode, where performance takes a much larger hit than in previous generations. This becomes evident in multi-core tasks. For example, on the M4 Pro Mac mini, the High Power mode is a staggering 55% faster compared to Low Power mode. In contrast, the difference between modes in single-core performance is more modest, closer to what we’ve seen in previous generations.
To illustrate the magnitude of this difference, I ran the same test on a previous-generation M3 Max MacBook Pro. There, the High Power mode was only 33% faster in multi-core performance compared to Low Power mode. This highlights the substantial performance reduction in the M4 Pro’s Low Power mode. Interestingly, while the M4 Pro delivers an 8% faster score in High Power mode compared to the M3 Max, the M3 Max actually outperforms the M4 Pro in Low Power mode by 27%.
While this might not impact most users since Automatic is the default mode, the drastic performance drop in Low Power mode is a notable change. One possible explanation for this shift could be Apple’s optimization of the efficiency curve. To maintain a reasonable power budget in Low Power mode, Apple may have needed to clamp down on the cores, resulting in a more significant impact on multi-core performance than single-core.
Another question that arises is whether this more restrictive Low Power mode extends battery life on the MacBook Pro. Apple boasts extended battery life with the M4 chips but doesn’t specify the source of this improvement. Since the battery size hasn’t changed, the more restricted Low Power mode could be contributing to this extended battery life. Although this might seem like Apple is exaggerating battery life figures, in the user’s experience, it might not matter. As long as users are aware that Low Power mode significantly reduces performance on the M4 Pro, they can make informed choices about their power mode settings.
With Apple’s M4 Max chips still largely untested, the question remains whether this performance drop in Low Power mode is exclusive to the M4 Pro or extends to the M4 Max. This is something I’m eager to investigate as soon as I get my hands on an M4 Max. Regardless, the performance differences between power modes in the M4 Pro chips are significant, and users should be aware of their implications before opting for Low Power mode.
