Build Your Own Computer : Step-by-Step Guide

To build your own computer is becoming increasingly popular. So why build it yourself when you can buy a pre-built one? The main thing is, you get exactly what you want. Companies making pre-built computers always reduce the price of the final product by using not-so-good components especially for things that you don't see in the specifications. Very often they also use motherboards with integrated graphics and sound which may look good in the specifications but is not desireable for someone who wants the most out of his/her computer. To build a computer is actually much easier than most people think. Pretty much all you have to do is to install the components inside the chassis by pushing them into slots and connecting a few cables. It can also be quite a bit cheaper than a pre-built one. Last but not least, it's a lot of fun choosing and putting everything together.

This is a step-by-step guide which you can follow while building it or you can jump to the specific section that you want to learn more about. In this guide I won't go into any specifications since they would rather quickly become outdated but I will recommend brands of the components.

First of all you need to acquire the chassis and the components. What components you need depends on what you are planning to use the computer for. The basic stuff are chassis, power supply unit, motherboard, processor with cooler, at least one memory module, at least one harddrive and you would probably also want a CD or DVD drive. If you're building a gaming computer, a high end graphics card and a nice sound card are also worth investing in.

The easiest way to choose the components is to start with the processor you want and then look for a motherboard with the same socket. Besides the correct socket you should also make sure that the motherboard has support for all the other components. I recommend that you read reviews of all the parts you choose so you know what to expect and that everything is compatible. Plan your purchases well. Since you are putting it together yourself you don't need to buy everything at the same shop. Looking around at different shops for the best prices on each component will save you more than you think.


Once you have the components, here are a few things that could be useful:

• A phillips-head (star/cross) screwdriver.
• ESD protection (e.g. an anti-static wrist wrap).
• Cable ties.
• A well lit workspace (preferably a big table).
• Plenty of free time.

As listed above, protection against ESD (ElectroStatic Discharge) is important. The components are sensitive and even a small discharge that you can not even feel can cause damage. Most shops where you can buy computer components should have some kind of ESD protection in stock. They are really cheap so it is an unnecessary risk not to use it.

You need a good work space because this is all much easier if you have a good overview. Do not start unpacking everything instantly! The components are usually packaged in ESD protection bags inside the boxes and you should let the them stay inside these bags until you need them.

Make sure you have plenty of free time. This can take a few hours (especially the first time). Do not go too fast forward and let it take the time it takes. If you rush you will likely make mistakes.

Read the manuals.

One of the coolest things about building it yourself is that you can choose the looks of it. It can be something way more interesting than a white/grey box. There are a big amount of chassis to choose from in all shapes, sizes and colours. Theoretically you could build a computer without a chassis but I do not recommend that. A chassis is important for protection of the components and for creating a good air flow.


Choose whatever you like but make sure it has enough room for all the components you want and that it has the same form factor as the motherboard (e.g. ATX). I would recommend you to not take the cheapest one you can find. The cheaper ones are made of weaker materials and therefore won't offer as much protection for the internals. They may also require a bit of modifying and the edges inside are usually sharp. For this guide I've choosen a high quality chassis from Lian Li. There are a few useful features you may want to look for such as a motherboard tray which makes it a bit easier to install the motherboard. Basically it allows you to install the motherboard on the tray and then slide the tray into the chassis instead of installing the motherboard directly in the limited space inside the chassis.


Below is a description of how to prepare the chassis.

	Let's start with unpacking the chassis.
	If the chassis of your choice did not come with fans or if you want to replace them with ultra quiet or LED fans it's recommended to start with that since it might not be as easy to reach where they are to be located once you have installed some of the other components.
	Install the fans in the chassis using screws.
	Here is one of the four LED fans I installed in this chassis.
	Connect the fans to the motherboard using 3-pin connectors. They can also be connected directly to the PSU using a 4-pin molex converter. You may need to skip this step until the motherboard is in place.

Som chassis come with a pre-installed PSU. If the one you choose do not, you will need to buy one separately. Note that the ones that come with a chassis depending on brand are often not very good so if you're building a high end machine you may want to buy a separate PSU even if your chassis already have one. Do not take the cheapest one you can find. This not where you should save money since this component powers all the other components and if it fails it might in the worst case scenario take it all out.


It's important that it has the same form factor as the motherboard (e.g. ATX). Make sure that it is strong enough for the machine its intended to power. If you're building a gaming machine I recommend you to get one that can generate at least 400W. I chose a 600W PSU from Zalman for this guide. Other brands to consider are Thermaltake, Coolermaster, Enermax, Antec, etc.


Below is a detailed description of how to install the PSU.

	Push the PSU into its tray in the chassis.
	Attach it using screws in the back of it.
	Here it is seated properly in the chassis.

As the name reveals this is a very central part of a computer. All components will be connected to it and the job of the motherboard is to relay information between them. A better motherboard does not automatically increase the performance of a computer but it might increase the limit for how much the components can be overclocked. Even if you do not plan to push your components to the limit by overclocking you may still not want to choose the cheapest one you can find because of its important role. Most motherboards have functionality built in like for example network adapters, RAID controller, graphics, sound, etc. Many of these can be very useful and good enough for the normal user. Note that all of them exist in more advanced versions in expansion cards if you need more of something. One thing you should avoid is motherboard integrated graphics. If you intend to play any kind of modern games or use other 3D software you will need a graphics expansion card.


When choosing a motherboard you need to make sure it has support for all the components you want to install on it and that its form factor (e.g. ATX) is compatible with the chassis and PSU. Another important thing to think about is upgradability. As an example, in a year or two you may want to upgrade to a faster CPU (processor). In the end it's cheaper to pay a little extra now to add support for that CPU instead of also having to upgrade the motherboard at the same time. I have choosen a motherboard from Asus. Other brands you may want to consider are Intel, Gigabyte, MSI, BFG, Abit, etc.


Below is a detailed description of how to install the motherboard.

	A Standard backplate often comes with the chassis but if you got a specific one with your motherboard you need to replace it with that one before installing the motherboard itself.
	Some CPU coolers require you to install a mount on the motherboard. Since this often includes a part to be installed on the back of it, it's the best to do this before attaching the motherboard to the chassis.
	Screw the standoffs into the chassis. These are used to prevent the motherboard from touching the inside of the chassis which could cause an electronic short.
	Attach the motherboard to the standoffs using screws.
	Here it is properly installed on the motherboard tray.
	Connect the power cable(s) to the motherboard. The number of and the type of power cables can vary so refer to your motherboard manual if you are unsure about which cables and connectors to use.
	Connect the cables from the front panel of the chassis to the motherboard.

The CPU is one of the most important components in a computer and a fast CPU is vital if you are building a high performance gaming machine. It interprets program instructions and does most of the actual work. Most CPU's now have multiple cores which is a great improvement over the older single core variants.



Make sure that the CPU is compatible with the motherboard socket and that the motherboard supports it. Besides the CPU itself you need a CPU cooler for it, most CPU's have a CPU cooler (usually a fan) included in the package. Thermal paste needs to be applied on the surfaces between the CPU and the CPU cooler. If thermal paste is not included you need to buy it separately. There are two big names in mircoprocessors and that is Intel and AMD. I've choosen an Intel CPU and a CPU cooler from Zalman for this guide.

If you intend to overclock the CPU there are usually a lot reviews with overclocking test results on different forums and websites that you should look at. Often you can go with a cheaper slightly lower performance CPU and still get it to speeds on par with or exceeding the expensive top-of-the-line CPU's out-of-the-box speeds. Overclocking has its drawbacks and is not recommended unless you know what you are doing.


Below is a detailed description of how to install the CPU.

	Here is the socket on the motherboard in which the CPU will be installed. In one corner of the CPU there is a triangle and a missing pin (or pad for LGA sockets). Make sure that this corner ends up in the corner of the socket which is also missing a pin/pad. The CPU only fits one way into the socket. It should drop in easily so do not try to force it as you might break the pins.
	Here is the CPU seated properly in the motherboard socket.
	Now lock it in by pushing the retention lever down. It might require some force but as long as the CPU is properly seated it won't take any damage from this.
	Here is the CPU locked into the motherboard socket.
	Apply a thin layer of thermal paste on top of the CPU. Make sure you get an even layer across the whole surface. Use just enough to exclude any air gaps. Too much paste separating the surfaces will have the opposite effect and degrade conductivity.
	Install the CPU cooler on top of the CPU and attach it using screws to the previously installed mount. If it is a traditional cooler with a fan you also need to connect its cable to a special connector on the motherboard which is usually a 3-pin.

The RAM is a type of data storage. It allows data to be accessed in any order without the physical movement of the storage device and that makes it fast. Most types of RAM lose their data when the computer is shut down so it is usually not for permanent storage instead it is used like a buffer between other storage devices and the CPU. Any programs that are currently running on a computer are partly stored in the RAM for fast access. A large capacity RAM will decrease loading times.


The most common type of RAM used in desktop computers is a version of DIMM DDR memory. DDR1 (also known as simply DDR) has been replaced by DDR2 which has twice the data transter rate of its predecessor. DDR2 is still around and is still very common but eventually it will be replaced by DDR3 which has four times the data transfer rate of DDR1. Currently you will most likely end up using either DDR2 or DDR3 depending on what the motherboard supports. The two biggest brands in RAM are Corsair and Kingston. There are quite a few other brands that are also very popular so look around before you make up your mind. I have chosen two RAM modules from Corsair for this guide.


Below is a detailed description of how to install the RAM modules.

	These are the RAM slots on the motherboard in which the RAM module(s) will be installed.
	Push the module down and the retention levers will go up and lock it in.
	Here is one RAM module seated properly in a RAM slot.
	If you have two matched dual channel modules they usually should go into two slots with the same color or else they will be run in single channel. Note that this might not be the case with all motherboards so refer to your motherboard manual.

An expansion card is basically a circuit board that can be inserted into an expansion slot on the motherboard to add additional functionality. A few examples can be graphics cards, sound cards, network adapters, modems, RAID controllers, etc. All these are optional and some of their functionality is integrated on most motherboards. What is included on motherboards may not be enough though depending on what you intend to use the computer for. As an example if you are building a gaming machine, a graphics card is pretty much required because motherboard integrated graphics will never come near its performance. If you are building a server machine to host websites, databases and/or other information you may want to use RAID to protect your data in case a harddrive fails. A motherboard integrated hybrid RAID controller may be enough for normal users but for a server you would probably want the extra safety and features an advanced hardware RAID controller can offer.


There are a few different types of expansion slots. Three are widely used and those are PCI, VGA and PCI-E. The latter one (PCI Express) is to replace the other two but they can still be found on many motherboards. Pretty much all high end graphics cards uses PCI-E but many other types of cards still uses PCI. An ATX form factor motherboard usually has up to seven expansion slots. Note that some expansion cards such as graphics cards with cooling installed may take the space of two slots. I have choosen a graphics card from Nvidia and a sound card from Creative for this guide. Another graphics card brand to consider is Nvidias biggest competitor ATI. Both brands have technology allowing you install multiple graphics cards on the same motherboard. Nvidia SLI and ATI Crossfire.


Below is a detailed description of how to install an expansion card.

	These are the expansion slots on the motherboard. Colours vary but here the blue slots and the white one right in between them are PCI-E. The really short white slot is also PCI-E but a slower variant. The other two white slots are PCI.
	Remove the slot cover next to the expansion slot you want to use.
	Push the expansion card into the slot.
	Attach it with the screw that previously held the cover in place.
	The expansion cards IO (Input/Output) plate at the back of the chassis when installed correctly.

The harddrive is where all the files are to be stored. You only need one but I would recommend you to get a harddrive with a lower capacity for installing the operating system (e.g. windows) and software and then a larger capacity drive for storage of other files. A great thing about having a second harddrive is that you can transfer files you want to save there from the first drive in case you need to format it. There are different sizes of harddrives but the one commonly used in desktop computers is 3.5". Inside a harddrive (they are sealed to protect them against dust) there are platters mounted on a spindle rotating at rates varying from 5400 to 15000 RPM. The higher the rate, the faster it can read the data. Note that even the slowest drives should be enough for the normal user and the faster drives are usually more expensive.


The most common types of interfaces for harddrives are IDE (also known as ATA or PATA) and SATA. There is also the more expensive SCSI and SAS which with their higher transfer rates are popular in high performance servers. For a normal desktop computer I recommend you to go with SATA since it is expected to eventually replace IDE. For this guide I have choosen three SATA harddrives from Western Digital of which two will run in a RAID configuration (common RAID levels listed below). A few other brands that could be worth considering are Seagate and Hitachi.


Common RAID configurations for normal users:

RAID Level 0   Also known as striping. Not true RAID because it does not provide fault tolerance. Basically what it does is to spread parts of the file system over several harddrives and read from and write to them all at the same time. It is used to increase performance and can in some cases if for example you are using two drives give you twice the transfer rate of one single drive. It is most popular in gaming machines but the performance gain is relatively small when running a game. Security is low and it gets lower the more drives are added to the array. If one of the drives fail you lose all data. Requires at least two harddrives and the number of drives must be even. If you would use for example one 20GB and one 30GB harddrive in RAID 0 you would get one logical drive with 40GB (20+20) and both physical drives would run only as fast as the slowest one of the two. That is one reason why it is the best to use identical drives.

RAID Level 1   Also known as mirroring. All the harddrives in the array contains the exact same data. Since every drive is a copy of the other, the system will keep running even if a drive fails because another harddrive in the array will take over. This is very useful when you have important files. Some RAID controllers can provide a performance increase when reading from the drives the same way as in RAID 0 but since it writes the exact same data to all drives the write performance would still be that of a single drive. Security is high and it gets higher the more drives are added to the array. If you would use for example one 20GB and one 30GB harddrive in RAID 1 you would get one logical drive with 20GB ((20+20)/2) and both physical drives would run only as fast as the slowest one of the two. That is why it is the best to use identical drives.

RAID Level 5   The file system is spread across all harddrives but the space equivalent to one of the drives is used for parity. If one single drive fails, the data blocks and a parity block from the working drives can be combined to reconstruct the missing data. Read performance should be almost as good as a RAID 0 array with the same number of drives but the write performance can be low in some cases. Security is relatively high but it gets lower the more drives are added to the array. If more than one drive fail at the same time you lose all data. Requires at least three harddrives. If you would use for example one 20GB, one 25GB and one 30GB harddrive in RAID 5 you would get one logical drive with 40GB ((3-1)*20) and all physical drives would run only as fast as the slowest one of the three. It is the best to use identical drives.

RAID Level 0+1   A nested RAID level that combines the performance increase of RAID 0 with the fault tolerance of RAID 1. Instead of separate harddrives there are sets of harddrives and each set are running in RAID 0 for increased performance. The sets are then being read from and written to in the same way as RAID 1 for fault tolerance. Security is relatively high and it gets either higher or lower depending on where you add more drives. If one harddrive from each set fails at the same time you lose all data. Requires at least four harddrives and the number of drives must be even. If you would use for example one 20GB, one 25GB, one 30GB and one 35GB harddrive in RAID 0+1 you would get one logical drive with 40GB ((20+20+20+20)/2) and all physical drives would run only as fast as the slowest one of the four. It is the best to use identical drives.

There is also RAID 10 (1+0) which is the same as RAID 0+1 with the exception that each set is run in RAID 1 and is then read from and written to in the same way as RAID 0. RAID 10 is considered to be more secure because of its better design where each harddrive directly mirrors a harddrive in another set instead of the whole set morroring another set. RAID 10 also does not decrease performance as much as RAID 0+1 when a drive fails and it should rebuild the array significantly faster after the failed drive has been replaced.

JBOD   Also known as spanning. Not true RAID because it does not provide fault tolerance. JBOD is short for Just a Bunch Of Disks and the purpose of it is to make several physical harddrives to appear as one single logical harddrive. Security is low and it gets lower the more drives are added to the array. If one of the drives fail you lose all data but it might be possible to recover some files from the still working drives. Requires at least two harddrives. If you would use for example one 12GB, one 15GB and one 20GB harddrive in JBOD you would get one logical drive with 47GB.


Below is a detailed description of how to install the harddrives.

	As I've mentioned you only need one harddrive but you can have as many as there are connectors for on the motherboard to suit your needs. I will be installing three. Two main harddrives in a RAID configuration and one larger capacity harddrive for files.
	Install them using screws in either the 3.5" slots or as in my case a harddrive tray.
	Connect the power and data cables to each harddrive.

An optical drive can read external media such as CD's, DVD's, etc. If you want to transfer data to external media, get one that has write capability (also known as a burner). To be able to install an operating system such as Windows you need an optical drive. If appearance is important, make sure the optical drives front has the same colour as the chassis.


The most common types of interfaces for optical drives are IDE (also known as ATA or PATA) and SATA. I recommend you to go with SATA since it is expected to eventually replace IDE. I have choosen an optical drive from Samsung. This isn't the most vital component so most brands should get the job done.


Below is a detailed description of how to install an optical drive.

	Remove the front panel and the slot cover from the chassis and then push the optical drive in.
	When in the correct position attach it using screws.
	Re-attach the front panel to the chassis.
	Connect the power and data cables to the drive.

It should now be completely assembled so it's time to test it. Before that, go through it all once and make sure everything is properly seated. When you are sure everything is as it should, plug the necessary cables into it (e.g. power, mouse and keyboard, monitor). Take a deep breath and push the button.

Important! Check that all fans are spinning, especially the CPU cooler fan. If one or more fans are not spinning, shut it down immediately and check the connectors. If you let it run without sufficient cooling there is a risk it will take damage from overheating.


As you can see it's a mess but it is the best to try it before putting the cables ties in there. It fired up perfectly the first time for me. If yours did not, do not worry! Very likely the cause is that something is not properly seated and if any of the components are faulty you can have them replaced under warranty.

Below is a list of possible causes to some problems you might have.

Nothing happended:

• Check the power cable in the wall outlet.
• Check the power switch on the back of the PSU.
• Check that the cables from the front panel are properly connected to the motherboard.
• Check the fuse for the wall outlet.

A faulty PSU can be the cause.

Continuous beeps:

• Refer to the motherboard manual for what the specific beep code means and then check that the component that is not responding is properly seated.

A faulty component can be the cause.

Power and HDD leds on the front do not light up:

• Check that the cables from the front panel are properly connected to the motherboard.

Harddrive does not spin up:

• Check the harddrives power connector.

A faulty harddrive can be the cause.

Nothing shows up on the monitor:

• Check that the monitor is on.
• Check that the monitors signal cable is properly connected to the computer and the monitor itself.

A faulty graphics card can be the cause.

Keyboard and/or mouse not found:

• Check the keyboard and mouse cables.

Displaying wrong CPU type/speed:

• Update the BIOS from the motherboard manufacturers website.

Displaying wrong RAM capacity:

• Check that the RAM module(s) are properly seated.

A faulty RAM module can be the cause.

Another problem:

• If you think you know which component is causing it, contact the support or use the support forum on the manufacturers website. Otherwise Google is your friend.

That's it! Simple, don't you agree? Now you may want to go into the BIOS (usually by pressing Delete when booting up) and take a look at the settings. Make sure that the components are set to run at their correct speeds and that the voltages are not automatically set too low.

When that's done the only thing remaining is to install an OS (Operating System) such as Windows.

Here are a few useful programs to test the performance of your newly built computer:

• CPU-Z
• 3DMark
• Memtest86
• Prime95
• Super PI
• Orthos

Some of these can also be very useful for testing results and stability when overclocking.

Have fun!