Apple MacBook Pro 15: How to get 2 more hours of battery life with this simple trick
For the original German news article, see here.
Sometimes, a seemingly random discovery is so fascinating that we feel the need to share it. In this particular case, we found a noteworthy oddity when reviewing Apple's current MacBook Pro 15 2017 (2.8 GHz, 555). In our first test, the 15-inch base model with 2.8 GHz Kaby Lake CPU and AMD Radeon Pro 555 GPU lasted for 8:31 hours in the Big Buck Bunny H.264 video test.
Almost 3 hours more with a differently equipped model
Not bad you might say, but apparently there was massive room for improvement we were not aware of at the time. In another review of a different MacBook Pro 15 2017 model (2.9 GHz, Radeon 560), we found it to last a total of 11:22 hours in the exact same test. Measuring inaccuracy and mean variation aside we were stunned and unable to find an explanation at first. Surely, the slightly different hardware could not possibly be the culprit, could it. So, we started digging.
Lower power consumption in full screen mode
We found the reason for this odd behavior after a while, and as expected it wasn’t a difference in hardware but in software. More specifically, the way the video was played using macOS’s Quicktime player. During the first review, the video was played in maximized window mode, whereas the second reviewer used full screen mode instead. Apparently, Apple has optimized the latter significantly: power consumption in full screen mode was much lower, as can be seen below. While the MacBook Pro consumed up to 11.5 W of energy during regular playback, it went down to between 9-9.5 W after a short spike in full screen mode.
Verdict: an extra feature film in full screen mode
What we can deduce from this is that the MacBook Pro’s video playback battery life can be greatly improved by watching videos in full screen rather than regular mode. To eliminate any doubt and error of measurement, we ran this test several times and found the MacBook Pro to last around 135 longer on average in full screen mode. However, this only applied to macOS. Using the Windows Media Player in Bootcamp, power consumption was at a much higher 28.2 W, and we found absolutely no difference between regular and full screen playback. The same applied to an ROG Zephyrus running Windows 10, which consumed 25.5 W of power regardless of playback mode. Consequently, battery life remained unchanged.
Update 08/10/2017: VLC
The power consumption in full screen mode also drops when you use VLC instead of Quicktime (on the MacBook running macOS). The idle result is 6.4 W. VLC consumes 17.4 W in a window, but only 14.9 W in full screen mode. Both values surpass the Quicktime results, but the phenomenon of the lower full screen consumption is still visible. macOS probably deactivates some background tasks.
MacBook Pro 15 2017 (2.9 GHz, 560)