Battery Life - How We Test:
Our custom HotHardware video loop test takes a 1080p HD video with a 16Kbps bit rate and loops it repeatedly, with 1 minute break intervals in between. A timer log file increments minutes of up-time, every minute -- along with the grand total -- before system shutdown is stored and logged. This is a lighter-duty test that is still a bit more strenuous than many office productivity tasks. During the test, we keep Windows 10 Quiet Hours enabled and the display has been calibrated with a meter on pure white screens to as close to 115 lux as possible. For the average laptop this is somewhere between a 40 - 60% brightness setting. Because laptop displays significantly affect power consumption and battery life, it's important to ensure a level playing field with respect to brightness of the display for battery testing. And, since many laptop displays vary in brightness at each respective setting in Windows, this calibration with a meter is critical to ensure all displays are set to as near identical brightness output as possible, before running battery tests.
Even with a 4K display, the Alienware m15 is able to last for more than a solid five hours before the battery reaches critically low power levels. Don't expect to get anything close to this while gaming, but if you working with light-weight tasks, like office productivity or video streaming, you should be able to use the Alienware m15 for a respectable amount of time before needing to plug in.
Alienware m15 Acoustics & Thermals
Dell designed the thermal solution for its Alienware m15 with a total of four copper cooling pipes. Two of these pipes run the length of the notebook and make direct contact to both the CPU and GPU. One of the remaining heatpipes makes contact with the GPU
and some of the graphics memory chips, whereas the fourth heatpipe connects to the CPU and the motherboard's VRMs to wick away thermals. The system has two fans set on opposite sides of the notebook that pull air in from underneath the system and push it out the back and sides. Although this thermal solution appears to do an excellent job of keeping the system cool and free from significant throttling, the chassis does get a bit warm to the touch while gaming. The keyboard of our test unit became noticeably warm when our game benchmarks were running, and the system was even warmer in other locations such as around the exhaust vents, and on the notebook's undercarriage. We kept the notebook seated on a table while we ran our tests, but we would imagine that this laptop could become uncomfortable if used for gaming on your lap. That said, typical use case suggests mouse and keyboard gamers will likely use the machine on a fixed surface.
The Alienware m15's cooling fans can also get a bit noisy under load, though this is common for most gaming laptops with this kind of firepower. The fans aren't so loud as to drown out sound from the speaker system, but it's noticeable enough. We also tested the speaker system of the m15 and were reasonably pleased by their performance. The m15's audio solution is reasonably loud and generates crisp high-end and midrange acoustics but with expected shallow low-end. We are also glad that Dell opted for a side-firing speaker design instead of bottom mounted speakers, as side-mounted speakers are less easily blocked.