Benji The PC is quiet at idle but opening a browser makes the CPU fan jump up for a second. Gaming noise is actually less annoying because it stays steady.
mosfet Look for fan response time or step-up delay in your motherboard fan controls. A very reactive curve will chase every short temperature spike.
sundown Also check which temperature sensor that fan is following. Take a screenshot of the curve and list the board and cooler so people can be specific.
Benji Will grab the board model and curve after work. I have only used the automatic fan tune so far.