Computer Case Form Factors

Mid Form Factor

It is the most common PC case for custom builds and stands 17-21 inches tall and supports a full-sized ATX motherboard. A typical mid tower can comfortably accommodate six to eight drive mounts,two graphics cards, and adequate cooling in space

 Full Form Factor

It is usually used for high-end computer such as PC servers and dedicated gaming PCs that need extra space for addition hardware components. Full tower provides more drive expansion, better cooling than the mid tower . It can range form 22 to 27 inches and supports full-sized ATX as well as EATX
motherboards.

Small Form Factor

It is usually comes in different shape, form cubes to desktop to normal tower, and supports mini ITX
motherboard with minimal drive-mounting options and sometimes supports add-in graphics cards. This is designed to be semi-portable and space-saving

Mini Form Factor

It is usually used for general-purpose PCs where requirement for additional devices is limited. Most mini tower are only suitable for use with adequate cooling. It supports a microATX motherboard