The physical and electrical specification for the connector USed by some of Intel' s microprocessor cards, currently (AugUSt 1999) the SEPPCeleron and the SECCPentium II. Slot 1 is a departure from the square ZIFPGA/SPGA sockets USed by Pentium and earlier processors, the processor being mounted on a card, with a 242-lead edge-connector. The Slot 1 specification allows for higher bUS rates than Socket 7. Slot 1 motherboards USe the GTL+ {bUS protocol}. See also Slot 2, Slot A. [bUS rates?] (1999-08-04)