Definitions for "Baby AT"
The form factor of most 386, 486 and many Pentium motherboards.  About 8.5" x 10".
The form factor used by most PC motherboards in the early 1990s. The original motherboard for the PC-AT measured 12in by 13in. Baby AT motherboards are a little smaller, 8.5in by 11in.
This is a motherboard form factor that has the same traits as the standard AT form factor, such as AT power connectors and keyboard input port. However, it is smaller in size, and can be utilized in smaller computer cases.
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