Datasheet

Cooling Methods 51
be more difficult for an untrained technician to work on, but they result in an almost
completely silent system.
Cooling Issues
A PC that works for a few minutes and then locks up is probably experiencing overheating
due to a heat sink or fan not functioning properly. To troubleshoot overheating, first check
all fans inside the PC to ensure they’re operating, and make sure any heat sinks are firmly
attached to their chips.
In a properly designed, properly assembled PC case, air flows in a specific path from the
power-supply fan through the vent holes. Cases are designed to cool by making the air flow
in a certain way. Therefore, operating a PC with the cover removed can make a PC more
susceptible to overheating, even though it’s “getting more air.”
Similarly, operating a PC with empty expansion-slot backplates removed can inhibit a
PC’s ability to cool itself properly because the extra holes change the airflow pattern from
what was intended by its design.
Although CPUs are the most common component to overheat, occasionally chips on
other devices, particularly video cards, may also overheat. Extra heat sinks or fans may be
installed to cool these chips.
Issues with liquid cooled machines can include problems with hoses or fittings, the
pump, or the coolant. A failure of the pump can keep the liquid from flowing and cause the
system to overheat. A liquid cooled system should also be checked every so often for leaks
or corrosion on the hoses and fittings, and the reservoir should be examined to make sure it
is full and does not contain contaminants.
Environmental Problems
Computers are like human beings. They have similar tolerances to heat and cold. In general,
anything comfortable to us is comfortable to computers. They need lots of clean, moving air
to keep them functioning.
Dirt, grime, paint, smoke, and other airborne particles can become caked on the inside
of the components. This is most common in automotive and manufacturing environments.
The contaminants create a film that coats the components, causing them to overheat and/or
conduct electricity on their surface. Blowing out these exposed systems with a can of con-
densed air from time to time can prevent damage to the components. While you’re cleaning
the components, be sure to clean any cooling fans in the power supply or on the heat sink.
To clean the power-supply fan, blow the air from the inside of the case.
When you do this, the fan will blow the contaminants out the cooling
vents. If you spray from the vents toward the inside of the box, you’ll be
blowing the dust and grime inside the case or back into the fan motor.
One way to ensure that the environment has the least possible effect on your computer is
to always leave the blanks in the empty slots on the back of your box. These pieces of metal
are designed to keep dirt, dust, and other foreign matter from the inside of the computer. They
also maintain proper airflow within the case to ensure that the computer doesn’t overheat.
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