tended motherboard) The PC motherboard that superseded the Baby AT design. The ATX layout rotated the CPU and memory 90 degrees, allowing full-length expansions to be plugged into all sockets. The power supply blows air over the CPU rather than pulling air through the chassis.
Introduced in 1995, the ATX was the first PC motherboard to not only include I/O support (serial, parallel, mouse, etc.), but to place all the connectors directly on the motherboard. Prior to the ATX, only the keyboard connector was attached to the motherboard.
Numerous variations of the ATX were subsequently introduced with both smaller and larger form factors, including the microATX, Mini ATX, FlexATX and Extended ATX (see PC motherboards
The ATX Motherboard
The motherboard glues all the components of a computer system together via its various slots, connectors and ports. In this case, Socket A is for an AMD Athlon XP CPU. DDR slots hold SDRAM memory modules, and the AGP and PCI slots hold the adapter cards. The back panel ports stick through the back of the case. (Image courtesy of ASUSTeK Computer Inc., www.asus.com)