A circuit board assembly, for example, a computer motherboard, for use in a liquid submersion cooled electronic device, for example, a computer, is configured to facilitate movement of the cooling liquid when the circuit board is submerged in the cooling liquid, thereby improving the heat transfer from heat-generating components on the circuit board. For a computer, a plurality of heat-generating components are mounted on the motherboard, including a plurality of processors, a plurality of memory cards, a plurality of graphics cards, and a plurality of power supplies. A pump for the cooling liquid can also be mounted on the motherboard.