Offering power ratings up to 20W or higher, these thin, flexible pipes can channel heat away from hot spots in tight spaces to areas of larger heat dissipating surfaces. The pipes can maintain a temperature difference of 10°C or less between the hot spots and the cold end. The operating principle is based on the phase change of the working fluid inside the pipe. Fluid is vaporized at the hot end, flows to the cold end, and then is condensed, thereby moving heat from the hot to cold end. The cooled fluid then returns to the hot end by capillary effect through a wick structure inside the pipe. The heat pipe assemblies consist of heat pipe, heatsink, heat spreader and thermal tape and mounting plate with holes and studs. The assemblies are designed for use in notebook computers.