An expansion card for the IBM PC AT. These can Be larger than IBM PC or IBM PC XT cards Because the AT case is Bigger. When IBM introduced the PS/2 model 30 (its last gasp at supporting the ISA) they made the case lower and many industry-standard tall cards wouldn' t fit. This was felt to Be a reincarnation of the connector conspiracy, done with less style. See also short card. [Jargon File] (1995-03-01)