A system may include a circuit board comprising a plurality of electrically-conductive layers separated and supported by layers of insulating material laminated together, wherein the plurality of electrically-conductive layers comprises a ground plane and the layers of insulating material comprise a surface layer having one or more openings through which the ground plane is exposed through the one or more openings. The system may also include a plurality of electrically-conductive pads formed on a surface of the surface layer and a cable comprising a first signal conductor mechanically contacted to a first pad of the plurality of electrically-conductive pads and a first drain conductor mechanically contacted to the ground plane through the one or more openings.