Building Your Own Computer – Part Three
Your motherboard should now be installed on the motherboard
plate. The reason for installing it on the plate before adding
the components like the CPU is to minimize the amount of handling the
motherboard receives. Once it's mounted on the plate, there will
be a very little need to touch the motherboard itself.
However, as we noted in the previous article, some cases do not have
a removable plate. In this case, you must install all the
components on the motherboard before installing it in the case.
Switches and Jumpers
Before installing the CPU and memory chips, you need to configure
your motherboard for bus speeds and voltage settings. This is
usually accomplished by changing a series of switches or placing
jumpers on various pins. You will need to refer to your
motherboard manual to find the correct settings.
There are two voltage settings that need to match your CPU -- core
voltage and I/O voltage. You may find the core voltage printed on
the CPU itself, and the I/O voltage also needs to be set according to
the CPU specs. Some motherboards detect voltage automatically, in
which case you do not need to worry about the settings.
The second setting for the CPU is the system bus speed. This
is set using a series of jumpers to match the speed of the CPU.
The jumpers are small pieces of plastic with metal contacts
inside. They fit over pins on the motherboard so that two pins
are connected. Consult your manual for the correct jumper
placement.
Depending on your motherboard, there may be other jumper settings
for the type of power supply, RAM speed, and enabling or disabling
onboard controllers. Check the manual for all the settings that
are required.
CPU and Cooler
Most CPUs are designed with an array of pins which fit into
corresponding holes on the CPU socket of the motherboard. The
latest CPUs from Intel are the contrary -- the pins are on the
motherboard and the holes are on the CPU. No matter which type of
CPU you have, before installing the CPU inspect the pins to make sure
that they are straight. A CPU with bent pins should be returned
to the retailer.
The CPU is held in place with a lever which exerts a small amount of
force on the pins. The lever is located on the side of the CPU
socket. Orient the CPU by lining up the clearly marked pin number
one. Let the CPU fall into place and secure it by replacing the
lever.
With the CPU in place, you can install the cooling unit. This
is the finned metal block with the fan attached to it. The block
is the heat sink – its large surface area dissipates heat quickly and
the fan blows cool air through the heat sink for maximum cooling.
The heat sink must come in direct contact with the CPU.
Because the CPU or the heat sink (or both) may have uneven surfaces a
pad or paste can be used to provide maximum contact between the
two. The thermal pad or thermal paste is placed on the raised
part in the middle of the CPU. If using thermal paste, a small
dab the size of the grain of rice is sufficient.
The cooler should come with a variety of attachments for different
CPUs. Refer to the cooler documentation for choosing the correct
ones. The attachments usually fit to the CPU socket with either 2
or 4 attachment points. You will probably have to use a little
bit of force to clip the cooler securely in place.
The cooler can now be connected to the power source near the CPU.
Look for a 3 pin power lead marked 'CPU Fan.'
