Start by putting your case down on your work surface, with the case door facing up, and open the case.

Motherboard

Find the motherboard standoffs (spacers) that should have come with the case. They are screws, usually brass, with large hexagonal heads that are tapped so you can fasten screws into the top. These hold the motherboard up off the case preventing a short-circuit. Set these aside.

Remove the I/O Shield from the back of the case where the ports on the back of the motherboard will fit, and put in the I/O Shield that came with your motherboard. There may be small metal tabs on the inside of this face plate, if so you may have to adjust them to accommodate the ports on the back of the motherboard.

Some case styles make it difficult to install the motherboard or the CPU with the power supply installed. If the power supply is in your way, take it out and set it aside (we’ll put it back in later).

Now locate the screw holes on your motherboard and find the corresponding holes on the motherboard plate (or tray) in the case. Put a standoff in each of these holes on the tray and position the motherboard so that you can see the holes in the top of the standoffs through the screw holes in the motherboard.

Now is the time to make sure the ports on the motherboard are mating with the backplate you just installed, and make any necessary adjustments. The small metal tabs are intended to make contact with the metal parts of the connections on the back of the motherboard and ground them, but you may have to bend these tabs a bit to get the ports all properly mounted, this is where those needle-nose pliers may come in handy.

Now fasten a screw through each of the motherboard screw holes into the standoffs underneath. These screws should be snug but not tight, there is no reason to torque down on them, hand tight is fine, otherwise you can damage the motherboard.

Once the motherboard is installed, it is time to plug the other components.

CPU

Installing the CPU, and the CPU’s heat-sink and fan, are by far the most difficult steps you’ll 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 heat-sink/fan combination, can require pretty firm pressure, so don’t be afraid to push a little harder if you’re sure everything is set up correctly.

The details of the installation process differ in slight but important ways for each manufacturer’s processors, and even within a manufacturer’s 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 is 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 dab of thermal paste the size of a grain of rice. Some people do like to wipe some onto the heat-sink’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 is 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 heat-sink, is to “lap” the heat-sink, 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 heat-sink 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 don’t touch it, the oil in your fingers can cause corrosion of the fresh surface) with a mirror finish. Some companies producing heat-sinks lap the surface themselves, so if the surface already looks like a perfect mirror, leave it alone. A lapped heat-sink 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 do not fit, check your setup – most likely something is wrong. After mounting the cooler, connect any power cables for the fan that is attached to 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, you’re over the hump, there just a few more easy pieces to go before that momentous first power-up.

Memory Slots

Next, you will need to install your RAM (random access memory). Find the RAM slots on your motherboard; they will look something like the picture on your left. To install the RAM modules, first push on the levers (white plastic in the picture) on either side of the DIMM socket, so that they move to the sides. Do not force them, they should move fairly easily.

Put the RAM module in the socket. Line up the notch in the center of the module with the small bump in the center of the RAM socket, making sure to insert it the right way. Push down on the module until both levers move up into the notches on the sides of the module. There should be a small “snap” when the module is fully seated. Although this does require a fair bit of force, do not overdo it or you may break the RAM module.

Take a good look at your seated RAM, if one side seems to be higher than the other, odds are it is improperly seated – take it out and try again. As you handle the RAM, try not to touch the copper stripes you can see along the bottom edge, as doing so is the best way to damage the part.

Start adding RAM at the slot labeled “Bank 0” or “DIMM 1”. If you do not have a stick in “Bank 0” or “DIMM 1” the system will think there is no RAM and will not boot.

On newer motherboards with 4 slots, you’ll see alternating colours. For example, slot 1 is blue, slot 2 is black, slot 3 is blue, slot 4 is black.

If you were to put 1 gigabyte of RAM in your personal computer, it is best to use dual channel 512MBx2 sticks. Put the first 512MB stick in slot 1, and put the 2nd stick inslot 3 (the two slots that are blue) – leaving slot 2 empty. This will give you better performance, vs. putting 1GB in slot 1, or two 512MB sticks in slot 1 and 2.

Power Supply
Installing your power supply is pretty straightforward, if it came with your case it was pre-installed and if you took it out earlier to get the motherboard in, now is the time to put it back. Otherwise a few moments of screwdriver work will get the job done. Generally there will be a bracket on the top of the case where the power supply is mounted and a few screws used to fix it in place. Some cases place the Power Supply differently, see the documentation that came with yours.

Some power supplies come with modular cables, so you can plug in only those you’ll be using, now is a good time to figure out what you’ll need and plug them in. Other power supplies have all the cables hardwired in, you’ll want to separate out the ones you’ll need and neatly coil the remainder somewhere out of the way.

If your power supply has a switch to select 115v or 220v make sure it is set properly, this is important. Many newer power supplies can automatically select and don’t have such a switch.

Once you get the power supply installed make sure you check the motherboard documentation carefully for the location of the power sockets. You may then connect the main power, a 20 or 24 pin plug, into the motherboard. There may also be an additional four or eight pin power lead that needs to be plugged in to the motherboard (the CPU power connector) usually located near the processor socket.

Video Card

If your motherboard has a built-in video adapter you want to use, skip this section.

If you have an AGP video card: Install the video card into the AGP socket. This is always the top expansion slot near the back of the computer. AGP slots are often brown, but can also be strange colours such as fluorescent green. Check the motherboard for levers (or similar devices) that are part of the AGP slot to help hold the card in place. These must be retracted before insertion of the card. Check the motherboard’s manual for information on how to use these devices (if your motherboard has one.) Push the card into the socket (AGP slots are often pretty tight, do not be afraid to push it until it is well inserted), then screw it in at the top of the metal bracket. If it has a power connector, connect it to a 4-pin molex connector. If it has a pass through, do not connect it to a hard drive.

If you have a PCI Express video card, install it the same way as an AGP video card, however the slot where it goes looks a little different having an extra spot on the slot as opposed to the 2 slot parts on an AGP slot. PCI Express slots used for video cards are commonly 16x as opposed to AGP 8x.

When your card is properly installed the line formed by the top of the card will be exactly parallel to the motherboard, if one side seems to be higher than the other, chances are that it is not fully inserted, press a little harder on the high side or pull it out and try again.

Installing Drive Jumpers

If you are using SATA drives there is no need to adjust jumpers — you can skip this section.

Before you install IDE/ATA (PATA) drives, you will need to set the drives jumpers. Each IDE/ATA channel can handle two drives, a master and a slave. Consult your drive’s instructions on how to set the jumpers. The jumper configurations are usually either printed on the back, or on the top of the drive. Drives can be configured in 2 ways: Drive Select or Cable Select.

• “Cable select”: Use this if you have 80-pin cables. Cable select automatically assigns slave/master based on the plug on the IDE cable the drive is plugged into. Put the jumper on CS.
• “Drive select”: If you are using a 40 pin cable, you must use “drive select”. Master/slave status is determined by the jumper. In this mode, configure the drive on the end connector as the master, and the drive connected to the middle connector as the slave. If the IDE channel has only one drive, check your motherboard documentation for the appropriate setting, which is usually master.

Note that Drive Select will always work, while Cable Select will only work if you have the proper cable.

Installing Drives

Next install the hard drive and optical drives.

How a drive is physically installed will depend on the case.

Most new drives are SATA (Serial ATA) which use simple, small cables for a data connection. The ends of the cables are L shaped, just look carefully at the cable ends and the connector on the drive and match them up. Only one drive can be connected to each SATA port on the motherboard. Some SATA drives have two different power ports – make sure you connect ONLY ONE of these ports to the power supply, connecting both can damage the drive.

Older drives have PATA (Parallel ATA) connections which use a flat ribbon (IDE) cable for data connection. When using an IDE cable, plug the two connectors that are closer together into the 2 drives, and the third to the controller or motherboard. The connector furthest from the board should be attached to the drive set as Master. Make sure the drive that you will install your OS on is the primary master. This is the master drive on the Primary IDE bus which is usually the IDE 40 pin port on the motherboard labeled “Primary” or “IDE 1”..

Next, plug a 4 pin molex power connector into each hard drive and optical drive. If you are installing the power connector to a SATA drive, some drives have the option of using either the SATA power connector (a flat about 1″ wide connector) or the standard molex connector; use one or the other, not both. Connecting both can break your hard drive. For better data transfer, you can purchase heat-protected high-end data cables at your nearest electronics store.

If you install a floppy disk drive, the cable is very similar to the IDE cable, but with fewer wires, and a strange little twist in the middle. Floppy drives do not have master/slave configurations. The floppy disk connector is not usually keyed, making it all too easy to plug it in the wrong way! One wire in the IDE cable will be colored differently: this is pin 1. There is usually some indication on the floppy drive as to which side this is. The power plug for a floppy is 4 pins in a line, but rather smaller than the standard hard drive power connector. Plug the end of the cable with the twist into the floppy drive (“drive A:”). Plug the other end of the floppy ribbon cable into the motherboard. If you install a second floppy drives, plug the middle connector into “drive B:”. The twist between drive A: (on the end) and drive B (in the middle) helps the computer distinguish between them.

Other Connections

In order to turn the computer on, you will need to connect the power button and while you are at it, you might as well do the reset buttons and front panel lights as well.
There will be a set of pins, usually near the front edge of the motherboard to which you will attach the cables sometimes already connected to the front of the case, or if needed supplied with the motherboard. Most of the time the plugs will be labeled as the pins they will connect to in the motherboard, there they can be difficult to read since the print is very small or you may not be in the right orientation to do so. The documentation that came with your case and motherboard should tell where these connectors are.

In addition, you can connect any case-specific ports if they are supported by the motherboard. Many cases have front mounted USB, Firewire and/or sound ports.

Earn a free Certificate of Completion for completing this course. Pass a 50-question test on this course with a score of 70 or higher and receive a certificate of completion. Visit our Computer Repair and Assembly Certificate of Completion page for more information.

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