Note: You are viewing an old revision of this page. View the current version.

ATX is an extension of the AT specification. It is a functionally optimal design for mainboard layout in PC architecture.

ATX specifies where the CPU is on the mother board, the size of the PSU, the position of the screw holes in the motherboard, the power connectors, where the holes on the back of the case should be, where the connectors on the front of the motherboard (for the front lights and buttons) should be etc.