I have a 2012 13-inch MBP w/ OSX 10.12.6, 2.5 i5 and 4GB ram I was running some cpu intensive applications, so the fan was spinning very fast and loudly. Suddenly, my mac made a loud clicking noise (I could feel it in the laptop as my hands were on the keyboard, it felt/sounded like something broke), and the fan turned off completely. I then closed most of my applications to avoid overheating. After a while, the mac made the clicking noise again (this time quieter) and the fan turned on and started to run at max speed, then slowed down to normal. Now, everything seems to be fine. Any ideas about what happened?