Hello everybody, I've noticed that since I installed Snow Leopard my Macbook's performance has dropped significantly. In the past few days my Macbook has shut down by itself 2 times. When I turn it on again, I saw that the temperature was oscillating around 77-80 C so I assumed it has shut down by overheating. I then start thinking that how come I don't hear the fan 's whizzing so I noticed that it is not working. Have any of you guys experimented this before with Snow Leopard? Have I missed something? Is it the fan?