I just upgraded from ubuntu 12.04 to 16.04 and my [AMD/ATI] RV770 [Radeon HD 4850] is getting very hot : 104°C !! The fans are spinning at full speed all the time !! The problem is that there is no activity on my PC : nothing is moving on the screen, there is 98% of Idle on CPU.
As I have a dual boot, if I boot windows on the same computer : all is getting back to normal : temperature and fan speed decrease
What should I do to not have my GPU burnt ?