Small form factor PC

Small Form Factor (SFF) is a motherboard form factor, such as ATX (the industry standard), m-ATX, or BTX. The form factor of a motherboard determines the specifications for its general shape and size. It also specifies what type of case and power supply will be supported, the placement of mounting holes, and the physical layout and organization of the board. Form factor is especially important if you build your own computer systems and need to ensure that you purchase the correct case and components.

Small Form Factor (SFF) represents a new footprint for computers — one where they're now small enough to disappear from the desk, or the exact opposite: often considered attractive enough in their brushed-aluminum and anodized-black finishes with bright blue LEDs to be a showpiece of status.

A typical small form factor PC is not quite a cube. A shoebox is a better approximation of its size, although this downgrading of size has little if any effect on performance.

Due to their small size, though, SFF systems usually are not particularly quiet or cool. The number of components commonly found inside of a mid-tower chassis being crammed into a chassis less than 1/3rd the size results in a compact system with a very large number of heat-producing components in extremely close proximity.

SFF systems usually ship as barebones units (chassis, motherboard, power supply), due to their proprietary rear backplane layout. Packing everything inside such a small space has lead to extensive manufacturer customization of the motherboard and chassis.