Installing the CPU, and the CPUs heatsink and fan, are by far the most difficult steps youll have to complete during your build. Here, more than anywhere else, it will pay to read the instructions carefully, look at the parts, study the diagrams that came with your CPU and/or third party cooling solution, and make sure you thoroughly understand what you are going to do before you try to do it. During the process, if anything does not seem to fit or make sense,put the parts down and look things
over carefully before you proceed.Some operations, especially installing the heatsink/fan combination, can require pretty firm pressure, so dont be afraid to push a little harder if youre sure everything is set up correctly.
The details of the installation process differ in slight but important ways
for each manufacturers processors, and even within a manufacturers product
line. Therefore, for these details, you should rely on the instructions that are
provided with the CPU.
The two things that go wrong the most often and most expensively (minimum
of a killed CPU, sometimes more) in building one’s own computer are
both related to the CPU and its cooler:
1. Switching the computer on “just to see if it works” before adding any
CPU cooling unit. Without cooling, CPUs heat up at extreme rates (a
CPU heats up anywhere between ten times and a thousand times as fast
as a cooking area on your stove!) By the time you see the first display on
the screen, your CPU will already be severely overheating and might be
damaged beyond repair.
2. Mounting the CPU cooler improperly. Read the instructions that came
with your CPU and cooler very carefully and ensure you are using all
components in the correct order and correct place.
If you buy a third party cooling solution for your CPU make sure you get
one that is compatible with the CPU you have. Most brands come with multiple
mounting brackets that will suit many different chipsets, but it’s best to check
for compatibility just in case.
If using thermal paste, apply it only to the CPU die (the square piece of
silicon in the middle of the CPU) and do so sparingly – most modern CPUs
take no more than a grain of rice sized dab of thermal paste. Some people do
like to wipe some onto the heatsink’s surface and then wipe it smoothly off so
that bits of it may get into tiny holes for better heat transfer. See Arctic Silver
Instructions for more info on how to apply and remove thermal paste/grease.
(It was written to be specifically for Arctic Silver paste, but the same techniques
can be applied to other brands of thermal paste.)
If using a thermal pad supplied with your cooler, make sure you remove any
protective tape from the die just before installing and do not get it dirty—and
do not combine thermal pads with thermal paste, it’s either one or the other.
Then, check that you install the cooler in the right orientation and that you
set it flat on the CPU die without exerting undue pressure on any edges or
corners—the latter can make small pieces of the die break off, killing the CPU.
One option you may consider, before installing the heatsink, is to “lap”
the heatsink, which means to smooth out the bottom surface. To do this, you
will need a very flat surface; a piece of thick window glass will work. Fasten
your sandpaper on the flat surface, invert the heatsink on the sandpaper and
sand in small circles, applying minimum pressure. Check frequently and when
you see a uniform pattern of scratches, switch to finer grained sandpaper (the
numbers go up as the sandpaper is finer, so something such as 220 is coarse
while 2000 will be very fine.) Remember that you are not trying to remove any
material, just polish out surface irregularities. If you get it right, you should
have a surface which feels completely smooth to the touch (but dont touch it,
the oil in your fingers can cause corrosion of the fresh surface) with a mirror
finish. Some companies producing heatsinks lap the surface themselves, so if
the surface already looks like a perfect mirror, leave it alone. A lapped heatsink
is more effective as it will have better surface contact with the chip.
Tighten the cooler using only the specified holding devices—if you did everything
right, they will fit. If they don’t fit, check your setup—most likely
something is wrong. After mounting the cooler, connect any power cables for
the fan that is attached onto the cooler.
As an aside to the instructions above, it has been my personal experience that
fitting the CPU and heat sink is best done on a supportive surface (a telephone
directory on a table in my case) prior to installation, to avoid excessive flexing
of the motherboard.
If you’ve got the CPU and its cooler installed, and the motherboard in the
case, youre over the hump, there just a few more easy pieces to go before that
momentous first power-up.