AT form factor

The AT form factor was the first modern form factor to be widely used. AT (Advanced Technology) was released in 1984 by IBM. Unlike the PC and XT form factors that preceded it, AT became a widely used design as a result of the booming home computer market in the 1980s. IBM clones made at the time began using AT compatible designs, contributing to its popularity. In the 1990s many computers still used AT and its variants, but ATX has been the most popular standard since 1997.
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