Heat pipes: the silent way to manage desktop thermal problems

The continuous increase in system power and decrease in available volume present challenges in desktop computer thermal management. Traditional desktop computer design has relied on natural convection from a heat sink placed directly on the processor. With increasing processor power, it has been necessary to add a processor fan to these local heat sinks. Components with moving parts are the most unreliable desktop computer components. The use of heat pipes may eliminate the use of processor fans and their inherent reliability concerns. A heat pipe heat sink is a passive cooling device that requires no moving parts, and operates silently and reliably. Heat pipe technology is emerging as a cost-effective thermal solution for the desktop industry. This paper explains the basic operation of heat pipes and provides a method to assess heat pipe heat sink design feasibility. Issues of heat pipe heat sink manufacturability and reliability are addressed. Fan sinks placed directly over the processor occupy the most valuable real estate in a computer and can interfere with the placement of add-on boards and other system components. Heat pipe sinks transport heat away from the obstructions and constraints of neighbouring boards to where it can be conveniently dissipated. The ability of the heat pipe to be formed to meet location and space availability and its characteristic low ΔT as a function of length permit the heat pipe heat sink system to provide the maximum effective heat sink surface area with minimum volume demand. The heat load can be conducted to open areas within the system