For the heat dissipation of processors, heat sinks with heat distribution plates underneath, thermal interface materials( TIM) or thermal paste are used for passive cooling, through which the heat from hot hotspots is better dissipated.
The thermal paste is applied relatively thinly to the underside of the heat sink or central processing unit and ensures direct thermal contact between the chassis and the microprocessor due to its good thermal conductivity (`lambda`) or low thermal resistance. The thermal conductivity is specified in W/mK and, in the case of thermal conductive pastes, lies between `2 W/(mK)` and `10 W/(mK)`; in contrast, air has a value of `0.02 W/(mK)`.
The processor's temperature is dissipated to the chassis via the thermal paste. The thermal paste compensates for the smallest unevenness of the contact surface of the heat sink or the chassis. It is mostly white and is supplied in syringes or tubes.