IBM Personal Computer AT

The IBM Personal Computer AT (model 5170, abbreviated as IBM AT or PC/AT) was released in August 1984 as the fourth model in the IBM Personal Computer line, following the IBM PC XT and its IBM Portable PC variant. It is based on the 16-bit Intel 80286microprocessor; the three earlier systems are all Intel 8088-based. The system sold for approximately US$6,000 (equivalent to $19,400 in 2025).

IBM did not specify an expanded form of AT on the machine, press releases, brochures, or documentation, but some sources expand the term as Advanced Technology, including at least one internal IBM document. The IBM PC AT was discontinued in 1987, prior to the release of the IBM PS/2 line.