Mini-ITX

Mini-ITX is a 170 mm × 170 mm (6.7 in × 6.7 in) motherboard form factor developed by VIA Technologies in 2001. Mini-ITX motherboards have been traditionally used in small-configured computer systems. Originally, Mini-ITX was a niche standard designed for fanless cooling with a low power consumption architecture, which made them useful for home theater PC systems, where fan noise can detract from the cinema experience. The four mounting holes in a Mini-ITX board line up with four of the holes in ATX-specification motherboards, and the locations of the backplate and expansion slot are the same (though one of the holes used was optional in earlier versions of the ATX spec). Mini-ITX boards can therefore often be used in cases designed for ATX, micro-ATX and other ATX variants if desired. Mini-ITX motherboards have only one expansion slot. Earlier Mini-ITX motherboards had a standard 33 MHz 5V 32-bit PCI slot, whereas newer motherboards use a PCI Express slot. Many older case designs use riser cards and some even have two-slot riser cards, although the two-slot riser cards are not compatible with all boards. Some boards based around non-x86 processors have a 3.3V PCI slot, and the Mini-ITX 2.0 (2008) boards have a PCI-Express ×16 slot; these boards are not compatible with the standard PCI riser cards supplied with older ITX (Information Technology eXtended) cases.