Question about Cooler Master Nepton 120XL

Depends the Rpm of the Fans, if they run on full speed, u can hear them, but if u run them on 1800Rpm they are really silent. 1800Rpm is still enough to cool my AMD FX 8350 (wich gets hot a lot)

I have one installed and I barely hear the fans even when the processor (i7 4790k, slightly overclocked) is experiencing heavy load (Gaming, ...). And most of the time the core temperature is <= 50°C. Although you will get significantly higher temperatures and more fan noise if you heavily overclock. Hope that helps you.