(ISA) The popular architecture for 1980s and early 1990s personal computer buses, such as the IBM PC,XT, & AT.
A personal computer bus architecture.
An expansion bus that was originally 8 bits wide running at a fixed 4.77 MHz. The width of this bus was expanded to 16 bits and the speed was increased to 8.33 MHz in 1984. The ISA bus has existed since the original IBM XT and can still be found in most modern PCs although there has been a concentrated effort to eliminate this "obsolete" bus for the last few years.