The BTX Form Factor is the latest in motherboard designs. The major
concern behind this design is the layout of heat-producing components such
as chipsets, processors, and graphics controllers. This design specifies that all
heat-producing components can use the primary airflow of the computer
thereby reducing the need for additional cooling fans that produce more
noise. The BTX Form Factor specifies better placement of components for
backpanel I/O controllers. Although it is smaller than the Micro ATX in size,
the BTX design is scalable and can be taken to the tower-size cases.

ATX stands for Advanced Technology Extended. This technology was
designed by Intel to allow easier expansion. With most of the components integrated
onto the motherboard, there is still sufficient scope to add additional
components. The expansion slots are located at right angles to the processor
and memory, which makes it easier to install full-length adapter cards. Moreover,
the processor and memory are located at the back of the card, in line
with the power supply, which makes better air flow for cooling them. It
supports soft power off support, meaning that the system can be turned off
using the operating system instead of using the power switch. It also supports
a 3.3 volt power supply from an ATX power supply. The power supply
connector is a single 20-pin connector.