Micro ATX

Micro ATX

microATX (sometimes referred to as µATX, mATX or uATX) is a standard for motherboards that was introduced in December 1997. The maximum size of a microATX motherboard is 244 mm × 244 mm (9.6 in × 9.6 in), but some microATX boards can be as small as 171.45 mm × 171.45 mm (6.75 in × 6.75 in). The standard ATX size is 25% longer, at 305 mm × 244 mm (12 in × 9.6 in).

Currently available microATX motherboards support CPUs from VIA, Intel or AMD.

Read more about Micro ATX:  Backward Compatibility, Expandability