Well i persumed it was a desktop but i must admit the wording as wrong using laptop instead of desktop haha,
Anyhow with the extremes you are talking about i would reall take it in for repair. Heat is a very big problem so using the laptop as little as possible will be the best idea. ITs something that requires more research into as in mean physical so if you can i would take it into a repair shop...sorry i cant be of more help