A method includes mating a first heat spreader and a second heat spreader, such that the first heat spreader at a mating surface and second heat spreader at a mating surface become parallel and adjacent. The mated first heat spreader and second heat spreader have at least one convection channel disposed therebetween. A process includes placing a first die in a first die recess of the first heat spreader, and placing a second die on a second die site on the second heat spreader. The process includes reflowing thermal interface material between each die and respective heat spreader. A package is achieved by the method, with reduced thicknesses. The package can be coupled through a bumpless build-up layer. The package can be assembled into a computing system.