Datasheet

72 Chapter 1
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Personal Computer System Components
Identifying Purposes and Characteristics
of Cooling Systems
It’s a basic concept of physics: electronic components turn electricity into work and heat.
The heat must be dissipated or the excess heat will shorten the life of the components. In
some cases (like the CPU), the component will produce so much heat that it can destroy
itself in a matter of seconds if there is not some way to remove this extra heat.
Most PCs use air-cooling methods to cool their internal components. With air cooling,
the movement of air removes the heat from the component. Sometimes, large blocks of
metal called heat sinks are attached to a heat-producing component in order to dissipate
the heat more rapidly.
Fans
When you turn on a computer, you will often hear lots of whirring. Contrary to popular
opinion, the majority of the noise isn’t coming from the hard disk (unless it’s about to go
bad). Most of this noise is coming from the various fans inside the computer. Fans provide
airflow within the computer.
Most PCs have a combination of these six fans:
Front intake fan This fan is used to bring fresh, cool air into the computer for cooling
purposes.
Rear exhaust fan This fan is used to take hot air out of the case.
Power supply exhaust fan This fan is usually found at the back of the power supply and is
used to cool the power supply. In addition, this fan draws air from inside the case into vents
in the power supply. This pulls hot air through the power supply so that it can be blown out
of the case. The front intake fan assists with this airflow. The rear exhaust fan supplements
the power supply fan to achieve the same result outside of the power supply.
CPU fan This fan is used to cool the processor. Typically, this fan is attached to a large
heat sink, which is in turn attached directly to the processor.
Chipset fan Some motherboard manufacturers replaced the heat sink on their onboard
chipset with a heat sink and fan combination as the chipset became more advanced. This
fan aids in the cooling of the onboard chipset (especially useful when overclocking).
Video card chipset fan As video cards get more complex and have higher performance,
more video cards have cooling fans directly attached. Despite their name, these fans don’t
attach to a chipset in the same sense as a chipset on a motherboard. The chipset here is
the set of chips mounted on the adapter, including the graphics processing unit (GPU) and
graphics memory.
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