A microelectronic assembly can include first and second microelectronic packages mounted to respective first and second opposed surfaces of a circuit panel. Each microelectronic package can include a substrate having first and second apertures extending between first and second surfaces thereof, first and second microelectronic elements each having a surface facing the first surface of the substrate and a plurality of contacts at the surface of the respective microelectronic element aligned with at least one of the apertures, a plurality of terminals exposed at the second surface in a central region thereof, and leads electrically connected between the contacts of each microelectronic element and the terminals. The apertures of each substrate can have first and second parallel axes extending in directions of the lengths of the respective apertures. The terminals of each microelectronic package can be configured to carry all of the address signals transferred to the respective microelectronic package.