In computing, form factor refers to the specifications of the motherboard and encompasses the physical size, mounting hole pattern, power supply type, the back-panel ports, and other design parameters.
The most common motherboard form factor size is ATX (Advanced Technology eXtended), which was developed by Intel in 1995 and still going strong. ATX boards are large, offer many expansion slots and room for onboard graphics and other perks, and fit well in the majority of modern computer tower cases.
There are over two dozen form factor sizes, but the majority of them are used for specific applications like embedded and server systems. Other commonly used form factor sizes besides ATX include microATX (popular for small form factor builds like compact and low-power home servers and media center computers) and Nano/Pico ITX boards (tiny boards used for low-power/silent media center builds and other embedded computer applications).
For more information on the differences between motherboard form factor sizes as well as what options to look for when motherboard shopping, check out our guide to picking the right motherboard for your custom PC.
- By Jason Fitzpatrick on 01/12/13