TheDTXform factor is a variation ofATX specification[1] designed especially forsmall form factor PCs (especially forHTPCs) with dimensions of 8 × 9.6 inches (203 × 244 mm).[2] An industry standard intended to enable interchangeability for systems similar toShuttle's original "SFF" designs,[3]AMD announced its development on January 10, 2007. AMD stated that the DTX form factor is an open standard, and is backward compatible withATX form factor cases. They also present a shorter variant namedMini-DTX which is smaller inPCB size of 8 × 6.7 inches (203 × 170 mm).[2]
The specification provides for up to 2expansion slots on a DTX motherboard, in the same position as the top two slots on an ATX ormicroATX board. The spec also provides for optionalExpressCard expansion slots on DTX motherboards.
DTX is a shorter version of ATX and micro-ATX, and Mini-DTX is a slightly longer version ofMini-ITX. Mini-ITX can have only one expansion slot, whereas Mini-DTX has the same width and can have two expansion slots.
| Specification | Year | Dimensions of motherboard | Expansion slots |
|---|---|---|---|
| ATX | 1995 | 12 × 9.6 in (305 × 244 mm) | 7 |
| microATX | 1997 | 9.6 × 9.6 in (244 × 244 mm) | 4 |
| DTX | 2007 | 8 × 9.6 in (203 × 244 mm) | 2 |
| mini-DTX | 8 × 6.7 in (203 × 170 mm) | ||
| mini-ITX | 2001 | 6.7 × 6.7 in (170 × 170 mm) | 1 |
There are several benefits DTX provides to reduce production costs.[4]