Christian de Looper/BGR If you're in the market for a new laptop because your current one overheats all the time, a model that handles heat properly should be your priority. Part of that comes down to the material in the computer's chassis: metal or plastic. When comparing both, metal is the right pick for cooling, as it dissipates heat from internal components across the entire laptop surface, which is why laptops like the MacBook Air don't even have a fan.  On the other hand, if you have or had an Intel MacBook, you probably remember how the chassis would get extremely warm because of its inefficient processor. In cases like this, a plastic laptop body is better, as it won't burn your lap, for example. Even though plastic is a thermal insulator that traps heat inside the chassis, the temperature is concentrated on the processor. Internal fans work hard and spin fast to push that hot air through the vents to lower the temperature.…