My PC fan starts up randomly and is super loud as if I was running a graphic intensive game (which I am not, nor am I even on the PC when it does this). I have a brand new Dell XPS 8930 i7-8086k processor with 64gb ram, 2tb hard drive, 1tb solid state drive, nvidia gtx 1080 with 8gb graphics. When the fan starts up, I tried ending as many things as possible in task manager without success, also changing power settings to less than 50% processor use did not affect it. The only way to stop the fan noise was to reboot. How do I fix this?