Micro ATX
The microATX motherboard is a standard that came out in 1997. It is also known as uATX. The smallest type measures 6.75 inches x 6.75 inches (or 171.45 mm x 171.45 mm). The maximum dimensions are 9.6 inches x 9.6 inches (or 244 mm x 244 mm). This motherboard has support for Intel, VIA and AMD CPUs.
Compatibility with ATX Boards
This motherboard has been created with full compatibility for ATX. This is possible because the mounting points are subsets of those utilized on ATX boards. Furthermore, the I/O panels are the same. For this reason they can be utilized on full scale ATX cases.
The microATX motherboard power connectors are usually identical to those used by ATX boards. This allows for the full use of ATX power. The chipsets used by both boards are also the same. This feature allows the boards to share the same components.
It should be noted though, that some microATX cases aren’t as big as those of ATX cases. For this reason they possess fewer expansion slots.
MicroATX Expandability
Its current specifications limit the number of PCI / PCI Express slots to a maximum of four. To save on space, manufacturers equip the motherboard with numerous peripherals. The addition of these peripherals can be used as a foundation for a small form factor.
An example of this type of microATX motherboard is the Asus A8N-VM CSM. This motherboard has AC97 audio, gigabit Ethernet and built-in graphics. By including these features, the slots they will use up can be assigned to others. This concept has proven successful that even ATX boards are adopting it.
The microATX case can support half a dozen SATA devices and up to four legacy IDE devices. The capabilities of its connectors can be maximized if it is mounted on the ATX case.
Size Comparison with Other ATX Motherboards
While the microATX measures (244 × 244 mm), the standard ATX is 305 × 244 mm. The flexATX measures 229 × 191 mm. The mini ATX measures 284 x 208 mm. The extended ATX (EATX) is 305 × 330 mm and the workstation ATX (WATX) is 356 × 425 mm.
Other Computer Form Factors
Besides the microATX motherboard, there are other computer form factors available. The form factors are listed along with the PCB (printed circuit board) size in mm. They are:
WTX 356 × 425, AT 350 × 305, Baby-AT 330 × 216, BTX 325 × 266, ATX 305 × 244, LPX 330 × 229, microBTX 264 × 267 and NLX 254 × 228 . Other form factors are DTX 244 × 203, FlexATX 229 × 191, Mini-DTX 203 × 170, EBX 203 × 146, Mini-ITX 170 × 170, EPIC (Express) 165 × 115 and ESM 149 × 71.
Other form factors available are Nano-ITX 120 × 120, COM Express 125 × 95, ESMexpress125 × 95, ETX/XTX 114 × 95, Pico-ITX 100 × 72, PC/104 (-Plus) 96 × 90, ESMini 95 × 55 and mobile-ITX 60 × 60.
The microATX motherboard specifications can change. This is due to innovations being made to the various components.