Source : Free On-Line Dictionary of Computing

Pin Grid Array
     
         (PGA) A style of {integrated circuit} socket or
        pin-out with pins laid out on a square or rectangular grid
        with a separation of 0.1 inch in each direction.  The pins
        near the centre of the array are often missing.
     
        PGA is often used on {motherboards} for {processors}, e.g.
        {Socket 6} and {Socket 8}.
     
        PPGA is "plastic PGA" (as opposed to ceramic?).
     
        See also {SPGA}.
     
        (2000-03-09)