The Spectre x360 15t is equipped with dual system fans which exhaust hot air through grills on the left and right side. The convertible is noiseless at idle and during light workloads like word processing and general browsing, so it's very suitable for noise sensitive areas. Average load with 3DMark 06 as well as high loads (stress test with Prime 95 and Furmark) can bump the fan noise to about 42 dB, which is towards the upper range in our comparison. Still, maximum fan noise occurs around 2 kHz, so the fans are not nearly as noticeable or annoying as they are on some smaller Ultrabooks and subnotebooks. The predecessor produces slightly more noise, but the Yoga 720 with GTX1050 gets nosier still and can reach 46 dB.
Witcher 3 noise is well-controlled however at about 36 dB, so gaming isn't affected as much, although we still recommend headphones for extended session. Coil whine is audible when running hard drive benchmarks and placing the ear close to the keyboard, but inaudible at normal distances.