An electronic system includes a first substrate including first solder bumps on a bottom surface, the first solder bumps having a first solder bump surface opposite from the bottom surface; a processor integrated circuit (IC) die including at least one processor mounted on a top surface of the first substrate; and a companion component to the processor IC. The companion component includes a second substrate, second solder bumps, and third solder bumps. The second solder bumps include a second solder bump surface, and the third solder bumps include a third solder bump surface at a different height than the second solder bump surface. The second solder bump surface contacts the top surface of the first substrate and the third solder bump surface is at a same height as the first solder bump surface.