This started after I just installed a Noctua NH-U12S Air Cooler on top of my Intel i7-8700K Coffee Lake 6-Core CPU and so far the core temps seems to be normal, being around average 30C while idle and then about 50-60C while playing a decent looking game. However, when I start up a game, like Warframe for example, I can hear slight constant buzzing coming from inside my the computer. As soon as I exit the game, the buzzing just immediately stops. Afterwards, I decided to see if the buzzing would still be present on an older looking game, like Postal 2 for example, and the buzzing still seemed to be present while playing that game, but not as loud as when playing Warframe. I don't know if it's suppose to be some kind of coil whine, but I'm not entirely sure. I want to know if it's a serious hardware problem that needs to be addressed as soon as possible or if it's normal and if there's something I can do to reduce that buzzing noise.
Build:
Motherboard: ASUS ROG Maximus X Hero (Wi-Fi AC) LGA 1151 (300 Series) Intel Z370 SATA 6Gb/s ATX Intel Motherboard
CPU: Intel i7-8700K Coffee Lake 6-Core
GPU: NVIDIA ASUS Strix GTX 1070
Memory: 16 GB
Build:
Motherboard: ASUS ROG Maximus X Hero (Wi-Fi AC) LGA 1151 (300 Series) Intel Z370 SATA 6Gb/s ATX Intel Motherboard
CPU: Intel i7-8700K Coffee Lake 6-Core
GPU: NVIDIA ASUS Strix GTX 1070
Memory: 16 GB