The need for forced-air cooling should be determined at an early stage
in system design. It is important that the design plans for good airflow
to heat-generating components and also allows adequate space and power
for the cooling fan.
The first stage in designing a forced-air cooling system is to estimate
the required airflow. This depends on the heat generated within the enclosure
and the maximum temperature rise permitted. The power dissipation figure used should be a worst-case estimate for a fully loaded system.