I don't know why, but these days my fans for some reason run throughout the day. When the fans start spinning the computer becomes extremely laggy. I have also tried running Macs Fan Control app after reading about it, but my system still hits 80°C. At that time it also freezes for 5 seconds to 2 minutes.
So any suggestions as to why it might be happening, and how I can fix it?
Running macOS High Sierra 10.13.3
MacBook Pro (15-inch, Mid 2012)
Processor: 2.3 GHz Intel Core i7