ATX and MicroATX (aka uATX) are the two most common but if you look for a third that you will frequently run across, it would be mini-ITX for the small-form-factor style of machines. I don't sell many of the mini-ITX designs through my store as most people who buy from me tend to prefer the larger, more flexible build designs. It all depends on what you require, however.
The most popular form factors are: -Mini ITX -Micro ATX -ATX -E ATX
atx,at,btx
NLX BTX ATX
NLX LPX Mini LPX
The three factors are : Using wires of specifications that match the power requirements of motherboard . Use the fan or heat sink properly. Do not use faulty devices with mother board.
The three form factors for desktop system boards are: ATX, and BTX and NLX
ATX
Some motherboard form factors (from smallest to largest in physical size) are: -Mini ITX -Micro ATX -ATX -E ATX
NLX, LPX, and Mini-LPX
The shape and layout of a motherboard (as well as the case) is called the form factor of the motherboard/case. Different form factors include AT (old & out of date), ATX (most common), BTX(up and coming), as well as uncommon form factors like NLX.
NLX
ATX, Actually todays most common motherboard form factor used is MicroATX