A riser assembly may include a riser cage and a riser card. The riser cage includes sidewalls, a base extending from the sidewalls, and mounting features to mount the riser cage to a chassis of the electronic device. The base is coupled to the riser card positioned on a first side of the base. The base includes an opening to permit the connector to extend through the opening to protrude partially beyond the opening to a location on a second side of the base where the connector can detachably connect to an expansion card installed in the riser cage between the sidewalls. The base contacts the connector around the opening to provide lateral support to the connector on opposing faces (e.g., first sidewalls) of the connector.