So I built my pc from parts I bought on Newegg in 2014, and for the past couple months it has been freezing or shutting down for no apparent reason. I thought maybe it was an overheating issue because I play games a lot so it tends to happen then, but it also does it when using Spotify, Chrome, and even sometimes when I have nothing up. The only thing I have managed to find out is that the CPU fan is almost always revved up, even at the desktop at times. The fan was like that from since I built it but I thought it was supposed to be like that, but I think I made a mistake believing that. So my question is: is my CPU/CPU fan bad and should I get a new one, or is it more than likely something else?