A high-speed electrical connector employs a plurality of electrical contacts held together by a dielectric frame. The contacts are electrically coupled to a substrate within the connector. A gasket may be disposed between the dielectric frame and the substrate and configured to block the flow of an overmold material between the dielectric frame and the substrate such that voids are formed between the contacts. The dielectric frame and the overmold may be made from materials containing silica aerogel. The voids and the aerogel materials result in reduced parasitic capacitance between the contacts enabling higher data transfer speeds.