A heat spreader and method for thermal management of a computer memory module by promoting natural convection cooling of the memory module. The heat spreader includes a frame surrounding a planar body adapted to be mounted to a memory module of a computer, and a grid defined in the planar body by a plurality of uniformly distributed perforations. The perforations extend through the planar body to allow natural convention between an interior space beneath the planar body and an exterior space above the planar body.