Build your own PC - A complete step-by-step guide

If this all looks a little much then check out our list of Best Deskop PCs

Over the last month we've tested every component you could need to build a PC, from cases to motherboards and CPUs to graphics cards. There were also plenty of options depending on your budget. Whether you want a cutting-edge gaming system, a home theatre PC or just something to do your tax return on, we’ve got you covered. See below for some example builds of our top picks.

Even if you’ve built a system before, this guide will be handy to keep you up to date with the latest components and methods, as things do change over time. You’ll find handy tips and tricks that might not only save you frustration during your next build, but will also result in a cleaner and more polished system. All the better to take advantage of that large viewing window on your PC case to show off your handiwork.

What follows is a step-by-step guide that runs you through the process of putting your system together, so that by the end you’ll have a fully working system you can be proud of. See opposite for a list of tools you’ll need for a stress-free PC building experience, and remember: take your time and enjoy. A day should be enough to put everything together, but we'd set aside a weekend if you want a really tidy build and to get Windows installed.

BEFORE YOU START

Before buying components, such as the case, graphics card or processor cooler, take the time to make sure everything is compatible. That means making sure you have an ATX case for an ATX motherboard, or that your graphics card will physically be able to fit in the case. This will help avoid frustration down the line.

Also check that you’ll have enough SATA cables for your disk drives (motherboards usually come with one or two, as will retail packed SSD kits). You may also need thermal paste if you’re using a third-party (not from Intel or AMD) CPU cooler.

TOOLS FOR THE JOB

You might be tempted to dive right in and get your hands dirty, but it’s worth taking a few minutes before you start to make sure you have everything you need for a smooth, trouble-free build.

Multi-head Screwdriver - A ratchet or electric screwdriver that supports a wide array of fitments will be more versatile than a typical crosshead screwdriver. They’re useful to have around the home for other tasks beyond building a PC as well. Choose one with a range of hex sockets that include at least 5, 6 and 7mm sizes. Magnetised tips will also help avoid losing screws down the back of the case.

Torch - A good source of light, be it a dedicated torch or a flashlight app on your smartphone, will help avoid frustration when building inside your case, especially if it’s all black inside. It also brings peace of mind during intricate tasks such as making sure you’ve lined up the processor the right way and when connecting peripherals to a PC under a desk. It’s also worth choosing somewhere well-lit for you build in the first place. 

Thermal Paste - Thermal paste allows heat to transfer efficiently from your processor to the attached heatsink and fan. If you’re buying a new full retail processor kit, the chances are you might not need this as the included cooler will likely have thermal paste pre-applied. However, it’s always useful to have thermal paste lying around for the future or if you’re transferring a processor from an old system.

Fine Pliers - These will be useful for removing and fitting the tiny jumpers on the motherboard that can be fiddly to hold with your fingers. They’ll also be invaluable when you need to hold parts in tight spaces or cutting wires or cable ties.

Cable Ties - You’ll want something to bunch the various cables together inside your case, not only to look nice and neat but also to help with airflow. We’d recommend using Velcro ties as these are easy to remove if you need to make changes. Zip ties can be an absolute nightmare to remove after you’ve attached them. Some electrical tape might also be useful for taping down cables to the case.

Crosshead Screwdriver - This will likely be your most used tool if your case doesn’t have thumbscrews. A screwdriver lets you fit and adjust most of the major components as well as removing the side panel on the case itself. Pick one with a long shaft to make it easier to reach recessed screws, while a magnetised tip will stop you dropping and losing any screws along the way.

Anti-static Wristband - This is designed to safeguard components from static, but we don’t think you really need this. The chances of killing a PC outright with static electricity are pretty small (we’ve never managed it in all our collective memories). Instead you can get rid of static by grounding yourself first.

Do this by touching the bare metal of your PC case, which is grounded if plugged into the mains (leave it turned off for now though). You can also ground yourself by touching an unpainted part of a radiator. Also try to work on a non-carpeted area to avoid static build-up, and it might also be a good idea to take off that woolly jumper.

Storage Drive - A simple USB flash drive will let you transfer drivers or software from another PC or allow you to flash a new BIOS if needed. A larger hard disk device will be perfect for taking full backups if you’re transferring data and programs from an old PC or laptop. You might also need a storage drive to install an operating system once all the components are installed.

A Hot Beverage - Building a PC can actually be quite therapeutic and relaxing, but if things do go wrong it can also frustrate. In both scenarios a nice cup of tea or coffee could be just what you need. Just make sure you keep it well away from your components to avoid any unfortunate accidents.

^ If in doubt, make tea, and try again later

How to ... Get the Case Ready

Step 1 REMOVE THE SIDE PANEL(s) - To get inside the case you’ll need to first remove the side panels. Some cases will use thumbscrews so this will be easy, otherwise grab your crosshead screwdriver to remove the screws. The priority will be the left side panel (when viewing the case front on). If you know there’s space to work behind the motherboard tray in your case for cable routing, remove the right panel as well.

Step 2 TAKE OUT ACCESSORIES - Most case manufacturers will place all the accessories and instructions inside the case itself for easy transportation. Make sure you take all of these out. It’s not uncommon for the screws to be in a box mounted in one of the hard drive bays, so be sure to slide this out using the removable tray. The end result you want is an empty, clean space inside the case for you to get to work. Make sure you keep all the screws within easy reach as you’ll need them later when installing the motherboard.

Step 3 REMOVE THE FRONT PLATES - If you’re planning on installing a 5¼in optical drive (or a memory card reader in the case’s 3½in external bay), you’ll first need to remove the port surround (or blanking) plates from the front of the case. It will probably be easiest to remove the front of the case altogether to do this, so consult the instruction manual. Most likely it will just need unclipping by pulling away from the case. Not all cases support an optical disc drive, so make sure yours does if you still need to use DVDs or CDs.     

Step 4 REMOVE THE BACK PLATES - If you’re planning on installing a dedicated graphics card or PCI/PCI Express card such as a TV Tuner, you’ll need to also remove blanking plates that cover the expansion slots from the back of the case. These will usually have screws holding them all in place, so reach for your screwdriver if you need it.

Only remove the ones you need, not only to maintain the attractive exterior but also to stop dirt entering the case. Some graphics cards require two plates to be removed. Keep hold of any screws you removed as you’ll need to use these to secure your graphics card or PCI/PCI Express card once inserted. If you’re having trouble working out which plates to remove, you can always take them out later when the motherboard is installed.

How to ... Install the power supply

Step 1 FIT SUPPLY ON TO SHELF - Increasingly, a lot of cases now position the power supply unit (PSU) in the bottom of the case. This can be preferable as the sheer weight of some PSUs means systems can be unbalanced when they’re mounted at the top. It can also make for neater cabling as the power cables don’t hang down into the case.

Which way round you install the PSU could be dictated by the case you use, so be sure to consult the manual. In some cases, you can decide to point the PSU air intake fan up or down. With the PSU fan pointed up towards the case internals, the fan can help draw warm air in and then expel it out of the rear of the case, helping to lower the temperature inside. Alternatively, you may also be able to have the PSU fan pointed down, where the PSU will draw in cool air from outside the case, allowing it to maintain a lower operating temperature and potentially expanding its lifespan.

If your case does take a PSU in the top there will be a small shelf on which the power unit can rest. Slide the PSU on to the shelf and push it back towards the rear of the case until it makes contact.

Step 2 SCREW IN SUPPLY - With the PSU in place, make sure the screw holes match up with the back of the case. Now it’s a simple matter of attaching the four screws to hold the PSU in place. Now is a good time to also attach the kettle lead and plug into a grounded wall socket so that the case is grounded. Don’t turn it on yet, though.

PLEASE NOTE - Power-related problems are often the cause of a system not booting. Make sure everything is properly connected and that you haven’t missed a power cable before pulling your hair out. Some PSUs let you switch the input voltage between 110V (US) and 230V (UK). Make sure yours is set correctly.

How to ... Install the motherboard

Step 1 UNPACK THE BOARD - Open up the motherboard’s box and remove its contents. Most likely you’ll find the motherboard itself inside an anti-static bag. Keep hold of the bag in case you need it later, but do not place components on this bag. You’ll also find a number of cables, most likely including a SATA cable or two, a driver CD and a port surround plate to insert into the rear of the case. Take these all out and put them somewhere safe for later on.

Step 2 CHECK THE PORT SURROUND PLATE - The port surround plate (often called the backplate) fits into the back of your case and gives you access to the ports on the motherboard, typically with pre-cut holes. Occasionally motherboard manufacturers will use generic plates that fit all of their motherboards, so you might need to remove specific port covers in order to match the actual connections available.

The easiest thing to do is to hold up the plate to your motherboard’s back connections to see which of them match, and then remove the ones you need. This could mean either twisting metal covers off, much like the expansion card blanking plates on the case, or it could require you to push a flap cover inwards to give access to the hole.

Step 3 INSTALLING THE PORT SURROUND PLATE - Now that all the holes line up with the connections on your motherboard, it’s time to attach the plate to the case. You’ll need to install the plate from the inside of the case pushing it outwards. The ridges should face out and the writing on the plate should be readable from outside of the case.   That way you know you’re definitely fitting it the right way. Also make sure it’s the right way up, with the PS/2 keyboard and mouse connections at the top and the audio connections on the bottom. Push the plate into the opening on the case with a little bit of force and it should click into place.

PLEASE NOTE - Third-Party Intel Coolers - If you’re using a motherboard for Intel processors and are planning on using a third-party cooler, make sure you install the motherboard backplate before you fit the motherboard into the case (see 'How to install an Intel processor', Step 4). Otherwise it will be a nightmare having to remove the motherboard unless your case provides rear access.

Step 4 MEASURE UP THE MOTHERBOARD - The next step is to install the motherboard inside the case. For this you will need to line up the motherboard with the pre-drilled holes in the motherboard tray. Make sure you have the right size PC case for your motherboard. For example, if you have an ATX motherboard it won’t fit inside a microATX case as it’s too large. A microATX board will usually happily fit inside an ATX case, however.

Take the motherboard and manoeuvre it into the case, lining it up with the port surround plate you fitted into the back of the case. Push the board in firmly so that it’s flush and fitted properly. The holes on the motherboard should now line up with the holes on the motherboard tray. Take a mental note of which holes are required and remove the motherboard, placing it in (not on) the bag it came in to be safe.

Step 5 FIT THE MOTHERBOARD STANDOFFS - Here is where the screws and accessories you put safely aside when opening up the case will come in handy. Have a dig through to find the motherboard standoffs. These are the tall, hollowed out screws that are typically made from brass. These standoffs are designed to hold the motherboard away from the case to prevent it shorting out when the motherboard contacts touch the case.

Simply screw these into the pre-drilled holes in the motherboard tray using the ones you identified in the previous step. Make sure these are screwed in tight and use one for each hole on the motherboard so that it’s held in securely. In some cases the standoffs might come pre-installed in the case but they might not be in the correct place for your particular motherboard. Follow the earlier instructions to make sure they’re in the right place; don’t leave any in the case that aren’t required for your board.

Step 6 INSTALL THE MOTHERBOARD - Once again slide the motherboard into the backplate and double-check you’ve installed the standoffs in the correct place. If you haven’t, remove the motherboard and fit any missing standoffs. With the standoffs in place, line the motherboard holes up and insert the screws, screwing them into the standoffs.   It’s best to do each corner of the motherboard first so that it’s held safely in place. Don’t tighten them all the way yet: just tighten them enough to keep the motherboard from sliding. With the corners done, insert the screws in the remaining holes and tighten them all so that the board is secure. Don’t over-tighten them as the board may crack.

Step 7 IDENTIFY THE ATX CONNECTOR - The motherboard draws power from the PSU typically using two connectors: an ATX connector and a secondary connector. Modern motherboards use a 24-pin ATX connection, which is easily identifiable as it’s the largest connection on the power supply. Older motherboards used a 20-pin connection, so your PSU might have an ATX connector with a detachable four-pin connector. Make sure that a full 24-pin connector is made by snapping the two cables together a bit like Lego.

Step 8 ATTACH ATX CONNECTOR - The ATX connector will only plug in one way as it has a small hook and clasp for securely attaching to the motherboard. Once it’s lined up correctly, attach the connection by applying a little downward force until you feel the clasp engage.   Give it a gentle tug afterwards to make sure it’s connected properly and give it a visual inspection to make sure it’s flush with the motherboard. A common reason for a PC failing to boot is that the power cables have been incorrectly attached, so here’s a good chance to use that torch.

Step 9 CONNECT THE SECONDARY CONNECTOR - Modern motherboards need a secondary power connector from the PSU. This will either be a four-pin or an eight-pin connection, depending on your motherboard. Check what type your PSU has as you might have to buy an adaptor. If your PSU is modular, make sure the correct power cable is attached. Some PSUs have an eight-pin connection that can be split in two. Much like the 24-pin connector, you’ll need to line up the connector the right way round and apply a little bit of force to properly attach it. A satisfying click will let you know when it’s in. 

How to ... Install the case fans

Step 1 IDENTIFY MOUNTING POINTS - Most cases come with at least one fan pre-installed, and they normally have two (excluding the fan built into your power supply). Typically one is installed in the front as an air intake and another at the back as an exhaust. That way cool air is drawn into the system and across your components, with the warm air expelled out of the back.

If you only have one fan, or are building a very powerful PC, then a second, third and even fourth fan might be a good idea. First you need to identify what size fans your case will support. Standard sizes are 80mm, 120mm, 140mm and occasionally 200mm, but consult the case’s manual or specifications.

Some mounting points are able to support two different sizes, such as 120mm or 140mm fans. Given the choice, it’s a good idea to go for the largest fan available. These will be able to move air far more efficiently and with less noise generated as they can operate at lower speeds. 

Step 2 ORIENTATE THE FAN - Fans only blow air in one direction, which means it’s important you pay attention to which way you mount the fan to the case.    You don’t want a fan that is supposed to act as an exhaust blowing air back into the case. Pay attention to any labelling on the fan itself. There might be an arrow on the top of the fan’s enclosure that indicates the direction of air, otherwise air will normally flow out of the side of the fan with the stickered labelling. Consult the instructions if in doubt.

Step 3 SCREW IN THE FAN - The fan should come with screws, or some may have been included with the case. Go through the accessories box you put aside earlier. The fan simply requires the installation of four screws to hold it in place. Tighten the screws so the fan is secure, but not so tight that you might damage the fan’s enclosure. It’s also a good idea to remove the fans occasionally for cleaning, so you don’t want to come back and find it won’t budge.   

Step 4  CONNECT FANS TO BOARD - The fans will need to be connected to the motherboard for power (see ‘How to connect the case and fan cables’).

PLEASE NOTE - Fan Layout - How you decide to place the fans around the case will be dependent on your case’s shape and design, but there are some general guidelines you should follow. The normal mounting points for fans are the rear, front, side and top.

Some cases also have a mounting point on the bottom if they have feet to provide the necessary clearance from the floor. If your system is going to be placed on the floor, it’s not advisable to install a fan in the bottom as this will draw in dust and dirt even with a dust filter installed.

You want to set up your fans so that they create a wind tunnel inside the case. It might also be a good idea to have more exhaust fans than intakes; that way a vacuum is created inside the case that draws in air beyond just the air intake fans. That means cool air will be drawn in from any other openings in the case.

A good starting point would be to have a front fan air intake, a side air intake, a rear exhaust and a top exhaust. All your components should then have cool air drawn across them and heat will be removed from the case.

How to ... Install an AMD processor

Step 1 OPEN THE SOCKET LEVER - AMD’s AM3, FM2 and FM2+ processors fit directly into a socket on the motherboard. The first step is to lift the metal lever to release the socket. The entire fixture will move slightly backwards and align the holes in the plastic socket with the connectors beneath.

Step 2 FIT THE PROCESSOR - The processor is a delicate component, so hold it from the edges and avoid touching the pins underneath. The processor will fit only one way into the socket so will require no force.

There’s a small arrow on the corner of the processor and a matching arrow on the corner of the socket. Line these two up and the processor will simply drop into place with zero fuss. If it feels as if the processor is not sitting flush with the motherboard, do not re-close the lever as this could damage the connections on the processor. Instead, double-check that the arrows are lined up and that the processor is squarely in the socket. Once you’re sure everything is set, close the lever again to lock the processor securely in place.

Step 3 APPLY THERMAL PASTE - You can skip this step if you’ve bought a new retail processor kit as the cooler will already have thermal paste pre-applied. If there’s what looks like a silver sticker on the bottom of the heatsink, this is actually a layer of thermal paste. Thermal paste helps to conduct heat away from the processor into the heatsink of the cooler, keeping temperatures under control.

If there isn’t any pre-applied paste, you’ll need to add your own. A small amount goes a long way so apply just a little on the top of the processor to start (no more than half a pea-sized lump). Use a thin bit of card to spread the thermal paste evenly across the top of the processor, avoiding getting any over the sides. Add more if necessary.

Step 4 FIT THE COOLER - The cooler supplied by AMD with its processor retail kits is relatively straightforward to fit, although it does take a little bit of force. There’s a large metal rod that extends beyond the sides of the cooler. This is designed to latch on to plastic tabs surrounding the processor socket on the motherboard.

First orientate the cooler so that the CPU cooler connection is closest to the cable for easy reach (see ‘How to connect the case and fan cables’). Then, take the cooler and open the lever so that the metal clips move freely. Place the cooler over the top of the processor and take the clip on the opposite side of the lever and attach it over the plastic tab so that it hooks up. Now take the other latch and, with a bit of effort, press down so that this also hooks on to the tab.

With both sides connected, close the lever to lock the processor cooler into place. This may also take a little bit of force. The cooler should be tightly locked to the motherboard, and you shouldn’t feel any wiggle.

PLEASE NOTE - Fitting an AM1 Cooler - If you’re installing one of AMD’s budget AM1 processors, the cooler-mounting process is different to the other socket types. AM1 uses push-pins that punch through pre-set holes on the motherboard rather than the locking clasps used for AMD’s other processor sockets. These can be a bit tricky to install if you follow the instructions included with the cooler, so use this guide instead.

To install the cooler, first line it up so that the two push-pins are above the holes in the motherboard. Push down on one of them until it goes through the motherboard, and insert the holding pin through the hole to keep it in place. Now do the same for the other corner of the cooler. This side will have risen up slightly so will be a bit trickier than the first. With both pins in place, the cooler will be securely locked to the processor. 

How to ... Install an Intel processor

Step 1 LIFT THE PROCESSOR CAGE - First you’ll need to remove the plastic cover on the processor socket to expose the cutout in the metal housing. This should simply pop out. To access the socket, you’ll need to unclip the handle that runs down the side of the socket. Lift this up to release the retaining clip on the main cage. Now lift the main cage up and out of the way to expose the socket. The pins for an Intel motherboard are on the board itself, so be sure not to damage these as bending them will stop the motherboard communicating with or powering the processor properly. 

Step 2 INSTALL THE PROCESSOR - Now line up the two cutout notches on the sides of the processor with the ridges in the socket. An arrow on the processor should line up with the corner of the socket that has a missing pin. The processor should drop gently into place and sit flush with the socket. If it doesn’t, and there’s some lateral movement, the processor is in the wrong way. Carefully lift it up and align again.

Close the metal cage and pull the retaining handle down. This might require a little bit of force, so again double-check the processor is positioned correctly before pressing down too hard. Slide the handle back into its locking position to securely put the processor in place.

Step 3 APPLY THERMAL PASTE - Chances are that if you bought a new processor with an included cooler, there’s already thermal paste pre-applied. If not, see ‘How to install an AMD processor’, step 3 (opposite) for how to apply your own.

Step 4 FIT THE COOLER - If you’re using a third-party cooler be sure to check the instructions as they might differ from standard Intel reference coolers that come with Intel’s processor kits. Some might require you to install a motherboard backplate to hold the cooler in place, especially the larger coolers.

The standard Intel reference cooler uses four feet that are secured into the holes surrounding the processor socket on the motherboard. Make sure these are rotated away from the direction of the arrow to start. It’s sensible to orientate the cooler so that the fan’s power cable is close to the CPU fan header on the motherboard.

Line up the four feet with the holes and start by pressing down on two diagonally opposite feet so that they lock into the motherboard. These should click into position so you know they’re secure. Now do the other two corners and the cooler should be securely in place. If you need to release the feet, simply use a screwdriver to turn the top of each foot as indicated by the arrow to release it.

How to ... Install RAM

HOW MUCH RAM CAN I INSTALL? Different motherboards have different numbers of memory slots, but also support different maximum amounts of memory. Typically a non-specialist motherboard with two memory slots will support a maximum of 16GB and a motherboard with four slots will support 32GB of memory. Unless you’re performing any particularly demanding tasks, such as video editing, 8GB is usually enough for day-to-day use.

You should also note which version of Windows you want to install (if this is your chosen operating system; see 'Installing an operating system'). Different versions have different memory limitations, as shown in the table below.

PLEASE NOTE - Dual-channel memory - Dual-channel architecture is a motherboard technology that essentially doubles the amount of available memory bandwidth, helping to remove any potential performance bottleneck when the memory is unable to match the processor’s performance. By installing a pair of memory modules in two matching banks, each module is able to access the memory controller separately to increase throughput bandwidth.

It’s generally a good idea to match the two memory modules for best compatibility, and many modules are sold as paired kits. If one module is rated at a slower speed than the other (for example, if one is 1,600MHz and the other is 1,333MHz), both will run at the slower speed in dual-channel mode. If you’re installing four modules they don’t all need to be identical, but make sure pairs match up accordingly and are installed in their respective slots.

Step 1 IDENTIFY THE SLOTS TO USE - If you want to take advantage of the performance increase of dual-channel architecture (there’s no reason you wouldn’t), the first step will be identifying which memory slots you should use as a matching pair. Frustratingly, motherboard manufacturers seem incapable of settling on a standard, so you might have to consult the manual if your motherboard has more than two slots.

Most memory slots are colour-coded, but whether you should install two modules in identically coloured slots or in different coloured slots will be down the manufacturer. The slots might also be numbered, so inspect the markings on the motherboard. These will make following the instructions easier.

Step 2 OPEN THE RETAINING CLIPS - Clips on each end of the slot hold the memory in place. You’ll need to open up the clips on each end by pressing down on them. They should pop open up to around 45˚ without much effort so that you’re ready to insert the memory module.

Step 3 LINE UP AND INSERT MEMORY - There’s an off-centre ridge on the memory slot on the motherboard and a slit on the memory module. Match these up to make sure you’re inserting the memory module the right way round. Provided you have the right memory for your motherboard, everything should line up.

Step 4 CLIP THE MEMORY IN PLACE - Once everything is lined up, press the memory into the slot by applying even pressure on each end.  The clips should spring back and lock into place with a click. Check the clips are nestled securely against the side of the memory module; if not, you might have to press down a little bit harder until there’s better contact. Repeat these steps for any other memory modules you need to install.

How to ... Connect the case and fan cables

Step 1 Connect CASE cables to the motherboard - There will be a number of different loose cables coming from your case that will need to be connected to headers on the motherboard. Connections for the power button, reset button and status LEDs are all grouped together. The cluster of headers you need might be labelled ‘Panel’ or ‘JFP1’. Consult your motherboard manual to be sure. Get the cables ready to be attached. They might have been tucked away behind the motherboard.

You can see an example of what you should be looking for below. If you have trouble connecting the fiddly headers by hand, use a pair of pliers to help you.

Step 2 Connect the POWER cable - One of the cables is the two-pin power cable, which will allow your case’s power switch to turn the system on. The cable will connect to a pair of pins that is among the cluster of other headers described above. If you’re lucky, the motherboard might have a ‘Power SW’ marking inscribed next to the relevant header. If not, you’ll need to consult a diagram in the motherboard’s manual in order to identify the correct headers. The power cable will slide over the two pins.

Step 3 Connect the RESET cable - If your case has a reset button, this will also need to be connected to the same group of headers. Again, you’re looking for the header for ‘RESET SW’; look on the motherboard or in the instruction manual. Slide the cable over the two pins as above.

Step 4 Connect the POWER AND HDD LEDs - These are the status indicator LEDs that flash on the front of your case to tell you it’s turned on or the HDD is active. These cables have plus and minus polarity, so it’s important they’re fitted to the correct header. The end of the cable will be marked for polarity. Consult the manual to make sure you connect the cable to the right header on the motherboard.

Step 5 Connect USB headers - If your case has front-mounted USB ports or a memory card reader, these will need to be connected to headers on the motherboard. The cable from the case will be labelled ‘USB’ and will be larger than the ones you’ve connected in the previous steps.

Look for headers marked ‘USB’ on your motherboard. This may be followed by a number, and there may be more than one header available, depending on your motherboard. It’s advisable to use whichever is closest to the cable’s origin to avoid messy cabling. The header on the motherboard is arranged by one row of five headers and another row of four, so one is missing from the corner. Make sure you look at the connector end of the case’s USB cable and line this up with the header on the motherboard. It should fit only one way.

Step 6 Connect USB3 headers - Your case may also have a USB3 port on the front, which is the much faster USB standard. This lets you connect faster USB3 devices such as flash drives, which will be able to transfer files much faster than plain old USB.

The USB3 header will look different to a regular USB header and there may only be one of them. If your motherboard is an older model, it may not have any at all, so check the specifications and manual. The cable will only attach in one way, so make sure you have it the right way round.

Step 7 Connect the AUDIO ports - The headphone and microphone jacks on the front of your case also need to be connected. The cable will be labelled ‘HD Audio’ on its connector. This might be labelled on your motherboard as ‘JAUD1’ or ‘AAFP’; consult the instruction manual if you’re unsure. This cable will again attach in only one way, so make sure you have it the right way round.

If your case has a built-in speaker for warning beeps, this will also need to be connected. The speaker headers on the motherboard may be in the same cluster of headers as the power and reset headers you connected earlier or nearby. The correct header will be labelled ‘Speaker’.

Step 8 Connect the FANS to the motherboard - Fans can be connected directly to the PSU, but it’s best to connect them to the motherboard instead. This way they can still get the power they need to operate but can also communicate directly with the motherboard. The motherboard will be able to control fan speed, which is useful if you want to strike a balance between case temperature and the noise generated by the fans.

Your fans will end in three- or four-pin connectors. Have a look on the motherboard for jumpers labelled ‘SYS_FAN’, ‘PWR_FAN’ or ‘CHA_FAN’. There will probably be more than one at different positions on the motherboard, so use whichever is closest to the corresponding fan.

Step 9 Connect the CPU FAN - The fan on the processor cooler we installed earlier will also need to be connected to the motherboard. Failure to do so might result in your motherboard giving you an error or the processor quickly overheating and automatically shutting down the system. Much like the case fans, the processor’s fan speed is controlled by the motherboard.

Connect the CPU fan to a connector labelled ‘CPU_FAN’ on the motherboard, typically located right next to the processor socket. Like the other connections, it will only plug in one way. This will either be a four-pin or three-pin connector.

How to ... Install a storage disk

Step 1 FIT STORAGE DISK INTO A BAY - Solid-state disks (SSDs) are a popular choice for storage these days, and most new cases have dedicated 2½in drive bays to accommodate them. In older cases you might have to install your SSDs in a 3½in bay using mounting brackets. Many SSD retail kits include these, or you can buy them online separately. As a stopgap you can pretty much put your SSD anywhere in the case, as it doesn’t vibrate or create much heat.

Some cases mount 2½in SSDs around the case. Consult the instruction manual to see if there are SSD vertical mounting points behind the motherboard tray, in the bottom of the case, or elsewhere. You’ll need to secure the SSD to these mounting points using the screws supplied with the case.

Whether you’re installing a 2½in or a 3½in drive, it helps if your case supports tool-less installation using drive cages or rails. If yours does, slide the storage disk in; the rails on the side should hold it in place. Some cases require you to screw in rails to the storage disk and then slide the entire assembly into the drive cage.

If you’re installing a 3½in drive, first locate a vacant 3½in drive bay on your case. This will most likely be in the front of the case but some cases might position them elsewhere, such as at the bottom of the case, depending on their shape and design. Don’t use an external bay (one that has a cutout in the front of the case) as these are designed to be used with memory card readers.

Step 2 PLUG IN SATA POWER - The SATA power connector is the wider of the two thin connectors on the disk drive, and needs to be connected to your PSU to provide power to the drive. Locate the SATA power cable coming from your PSU (or attach it if your PSU is modular). Connect this to the SATA power connector on the hard disk itself. Look closely and you’ll see it’s an elongated ‘L’ shape, so it will only connect one way. Make sure you connect it straight in, avoiding any downward pressure, as this could damage the connector.

Step 3 CONNECT the SATA DATA CABLE TO the STORAGE DISK - The other thin connection on your SSD or hard disk is the SATA data connection. This is what carries the data between the storage disk and the motherboard. Your motherboard will come with SATA cables included, so locate the accessories you put aside earlier. Your hard disk may have also come with SATA cables if it was a retail kit.

The SATA cable may terminate in a straight connection, or it may be an angled L-shaped connection. The latter is better for neater cabling as the cable isn’t angled straight out of the connector. Like the power connection, the cable will only connect in one way. Push it straight in and you should feel a subtle click to let you know it’s securely connected.

Step 4 CONNECT the SATA CABLE TO the MOTHERBOARD - Now you need to connect the other end of the SATA cable to the motherboard. First locate the SATA connections on your motherboard. These are usually at the bottom right of the board. Some of the connections may be facing sideways and placed along the edge.

Each SATA port should be numbered, which will let you know the motherboard’s default boot order (unless you change the boot priority in the BIOS). Lower-numbered SATA ports will boot first. Therefore if you’re installing more than one disk drive, make sure that the disk drive you’re using as a boot disk (the one on which your operating system will be installed) is plugged into the lowest-numbered port.

You may need to make sure all the SATA ports behave in the same way, as some may be reserved for special uses such as RAID arrays, and some may be the slower SATA2 standard. You’ll want to connect an SSD to a SATA3 port as they benefit from faster transfer speeds. The SATA cable will only connect one way to the motherboard and will click securely into place.

M.2 and MSATA

M.2 and mSATA SSDs are both relatively new technologies, and they’re a great choice as a fast system disk for your operating system. These connect directly to a dedicated socket on the motherboard, usually near the middle of the board. They’re not just great for speed, but also for neatness as no additional power or data-transfer cables are needed.

To install an mSATA SSD, match the ridges and notches on the mSATA SSD and the socket. Insert the drive at around a 45˚ angle until it’s flush with the socket. Then lay the mSATA SSD flat. The disk will either be held in place with retaining clips, similar to the memory modules, or you may need to install screws. Use the screws included with the mSATA SSD.

The process for an M.2 SSD is very similar. You may need to remove an existing pre-installed retaining screw from the motherboard before you install the M.2 SSD. Once the SSD is installed you can re-install the retaining screw at the end to hold it in place.

^ M.2 and MSATA look to be the future for PC storage as they simply plug into your motherboard

How to ... Install an optical drive

Step 1 FIT THE DRIVE - Many new PCs and laptops no longer come with optical disc drives. If you want an optical drive for reading DVD-ROM or DVD and Blu-ray movies, you’ll need to make sure your case supports external 5¼in drives.

The standard way to install an optical drive is to insert it from the front of the case, rather than the inside as with your hard disks.   The first thing you’ll need to do is to remove the case’s front panel. Chances are this will just pop off, but consult your manual if this isn’t the case. Slide the optical disc drive into the drive bay and push it back until the front is flush with the case. Screw-holes on the side of the drive should line up with holes in the drive bay. Secure the optical drive in place using four screws, much as you would with your hard disk. You should use four screws in total, two on each side.

Step 2 PLUG IN SATA POWER CABLE - Just as you did with your storage disks, you’ll need to connect your optical drive to the PSU using a SATA power cable. Attach the cable and make sure it’s inserted all the way (see the image in ‘How to install a storage disk’, opposite, to know what to look for). Older optical drives may use a Molex cable, one of which should be available on your PSU. 

Step 3 CONNECT THE SATA CABLE TO THE OPTICAL DRIVE - Now connect a SATA cable to the back of the optical drive as you did with your storage disks. If you’ve installed a few storage disks you might be running low on SATA cables unless your optical disk drive had one included, so make sure you have enough. You can pick up a SATA cable for as little as £1 from www.ebuyer.com.

 Step 4 CONNECT THE SATA CABLE TO THE MOTHERBOARD - Locate the SATA ports on your motherboard that you used earlier for your storage disks. If your motherboard has a mix of SATA2 and SATA3 ports, use a SATA2 port for your optical drive as they don’t benefit from faster speeds. You can then save your SATA3 ports for future additions. 

How to ... Install a graphics card

Step 1 REMOVE the BLANKING PLATE - We showed you how to remove the rear blanking plates on your case in ‘How to get the case ready’. It’s a little easier to do this when the case is empty, but if you’ve already fitted your other components, it’s not too late; follow the instructions there. If your graphics card is double-height, you’ll need to remove two blanking plates.

Step 2 IDENTIFY THE PCI-E x16 SLOT - Graphics cards connect to a PCI Express x16 (PCI-E x16) slot on your motherboard. This is usually the longest slot on the motherboard next to the blanking plates. Your motherboard may have more than one PCI-E x16 slot, allowing you to install more than one graphics card for increased performance. If you’re only installing one graphics card you’ll want to use the slot nearest the top of the motherboard, towards the processor. This is because this slot will run at full x16 speed whereas other slots may run only at x8 or x4 speeds.

Step 3 FIT THE GRAPHICS CARD - To fit the graphics card you’ll need to line up the card with the slot in the drive, with the output connections towards the vacant blanking plates you removed earlier. The graphics card’s fans will normally be pointing towards the bottom of the case.

Push the graphics card down and towards the back of the case so that the display output connections are available from the back of the case. Exert even pressure down on the graphics card into the slot.   A retaining clip towards the end of the slot will click into place when the graphics card has been successfully connected. The whole of the graphics card’s connector should sit level within the motherboard slot.

Step 4 SCREW THE CARD INTO PLACE - You’ll need to now insert the screw(s) you saved earlier when removing the backplate(s). This will secure the graphics card to the rear slot and stop it from moving around or coming loose.

Step 5 PLUG IN THE POWER Most graphics cards require separate power from the PSU using either a six-pin or an eight-pin power connector. Some of the more power-hungry models might even need two connectors. Any modern power supply will have these connectors; otherwise a Molex-to-PCI Express adaptor is often bundled with the card. 

How to ... Install expansion cards

Step 1 IDENTIFY A SPARE SLOT - Depending on what you’re planning to install, you may need to install software before you fit your new card. This means it should be the last thing you do, after everything else has been set up and you’ve installed an operating system.

When you’re ready, locate a PCI Express (PCI-E x1) or PCI slot, depending on the card you’re installing. Not all motherboards have both, so check what’s available on your board before you buy an expansion card. Look at the image on the right to identify which slots you have . It’s best to try and leave some space between components to help with airflow, so use the slot furthest away from the graphics card if you have one installed.

Step 2 REMOVE THE BLANKING PLATE - You might have already removed the blanking plate while initially setting up the case. If not, now is the time. It will either be individually screwed in or held in place by a retaining bar. Sometimes the blanking plate will lift straight out, but you might need to rock the blanking plate out and break it off the case. Be careful with any sharp edges and be sure to keep hold of the screw for later.

Step 3 INSTALL THE CARD - The procedure for installing a PCI or a PCI Express card is the same. Line up the notches and ridges between the card and the slot; they will only fit one way. Apply some downward force to get the card to sit securely in the slot. Unlike the PCI-E x16 slot used for the graphics card, there’s no retaining clip at the end, so don’t worry about not feeling a click when the card is seated. Just make sure the entire card connector is level within the motherboard slot down its entire length.

Step 4 SCREW THE CARD INTO PLACE - With the card fitted, secure it in its slot using the screw you retained. This will stop the card moving when you connect anything through the rear of the case, such as external antennas.

Step 5 PLUG IN THE POWER - Most PCI and PCI Express expansion cards don’t need separate power, instead drawing what they need from the motherboard. If your card does require power, connect it to the PSU using whichever cable it requires.

How to ... Route your cables

Step 1 TIE-OFF EXCESS CABLES - Some cables, such as the front panel audio, branch into two connections when you only need to use one of them. This usually means that a second connection branches off just before the main cable terminates. Fold the excess cable back on itself and tie it down to the main cable so it’s out of the way. Do this for any other cables around the case, such as the PSU’s SATA power cables.

Step 2 BUNDLE TOGETHER CABLES - Any cables close to one another should be bundled together to make one thick cable. Use several ties along their length. You can also group together several smaller bundles where possible. It’s not advisable to use zip ties as these are a nightmare to remove.

If your case lets you route cables behind the motherboard, see the next step. If not, try to route as many cables as possible along the edge of the case so they’re out of the way. You can use electrical tape for this. You can also tie cables to the drive bays. Keep the cables clear of any fans as they can cause an obstruction.

Step 3 ROUTE CABLES BEHIND BOARD - Not all cases let you route cables behind the motherboard, but if yours does it’s definitely something you want to take advantage of. This takes them out of the airflow path across the components, allowing the fans to work more efficiently. If you have a window on the side panel, it also makes your PC more attractive.

Your case may have several rubber-covered passthrough holes through which you can route the cabling. Route any excess cable through one of these holes towards the back of the tray and then back round again to the front through another hole, a bit like sewing a stitch, so that the cables can be connected to components or the motherboard. There will be several passthrough holes, so use whichever is closest to the cables’ intended destination to reduce the amount of cable on show.

Be sure to run the cables in such a way that they sit flat against the back of the motherboard tray. This is to ensure the side panel isn’t blocked by bulging cables and that you’re able to put it back on properly.

How to ... Put the case back together

Step 1 FINAL CHECKS - Now that everything is attached, now is a good time to do a final check. Make sure all the motherboard connections are securely in place. One of the most common reasons for a boot failure is a loose cable, so it pays to double- or even triple-check. Similarly, make sure all the components, such as the RAM and graphics card, are seated correctly. Make sure there’s no loose cabling that could obstruct the fans. Go back to ‘How to route your cables’ if necessary.

Step 2 ATTACH THE FRONT OF THE CASE - With the final checks completed, you’re ready to re-assemble the case. If you removed the front of the case to install an optical drive or attach a fan, now is the time to re-attach it. It should just clip back into place, but consult the manual if your case is different.

Step 3 ATTACH THE SIDE PANELS - Next up are the side panels. To re-attach them on most cases you simply slide them into place so that the clips line up with the grooves. Re-insert the screws to hold the panels in place either using thumbscrews or a screwdriver. If you cabled correctly, you shouldn’t have any problems with the side panel behind the motherboard tray.

How to ... Connect peripherals

Step 1 CONNECT THE KEYBOARD AND MOUSE - You’ll need to connect a keyboard and mouse before you get started. Older keyboards and mice use PS/2 connections, which your motherboard should have. Most new keyboards and mice use USB, or a USB dongle if they’re wireless. Connect either of these to the rear USB ports.

Step 2 CONNECT SPEAKERS - If you have a set of speakers you want to connect, now is the time. If you’re simply connecting a pair of stereo speakers, connect the 3.5mm audio cable from the speakers into the green audio jack on the motherboard or into your dedicated sound card.

Surround-sound speakers require a few more connections. Simply match the colour-coded cables with the matching coloured ports for the satellite speakers and subwoofer.

Step 3 CONNECT A NETWORK CABLE - If you’re planning on using an Ethernet cable for networking, connect it to the Ethernet port on the motherboard. The other end of the cable can be connected to your router, HomePlug adaptor or Wi-Fi bridge.

Step 4 PLUG IN THE MONITOR - Modern PCs have numerous options for connecting a display. Most motherboards have onboard graphics, which are fine for most tasks. However, if you’ve invested in a graphics card to play games then you’ll want to use the outputs it provides. You’ll have a selection of outputs, including VGA (also known as D-sub), DVI and HDMI, plus possibly DisplayPort. The last three are digital connections, while VGA is an older analogue connection.

Most modern monitors support DVI and HDMI inputs, some also have DisplayPort, and some older monitors may only support VGA. DVI and HDMI are largely interchangeable, and you can buy a DVI-to-HDMI cable. You can also output audio over HDMI, so if you want to use monitor speakers or are connecting your PC to a TV it’s the best choice.

Monitors with high resolutions over 1,200x1,080 are a bit more complex. If your graphics card or integrated graphics supports the latest HDMI 1.4 standard, you should be fine to connect your monitor using HDMI. DisplayPort is another good option for high-resolution connections, or you can use a dual-link DVI output.

If your monitor only supports VGA inputs, your motherboard should provide one. Your graphics card probably won’t have a dedicated VGA output, but you can still hook up your monitor via a DVI-I output, which includes the extra pins for carrying the analogue VGA signal. A DVI-to-VGA converter is often included in the graphics card box.

How to ... Install an operating system

Step 1 CREATE A BOOTABLE FLASH DRIVE

If you’re installing an operating system from a CD/DVD, such as a Windows 8 retail pack, you can ignore this step and proceed to Step 2. If you’re planning to install an operating system from a hard disk or USB flash drive, however, you’ll need to set it up as a bootable drive with an operating system installation on it. You’ll need to use another PC to set it up.

Windows

Windows 8.1 is the best operating system to install right now, and you’ll get a free upgrade to Windows 10 when it’s available. You’ll need to have a full retail copy to install it on your new PC; an old product key and restore disc from a previously bought PC or laptop won’t be licensed for use on your new hardware.

If you have an old retail copy of Windows 7 (again, not a copy that came installed on another PC or laptop), then that will suffice as a stand-in operating system until Windows 10 launches later this year. Just be sure to install all the security updates via Windows Update before you start browsing online.

If you’ve lost or scratched your retail Windows install disc, then you can download an ISO image of it from Microsoft and create a new one. To do so, follow our instructions at How to download & make Windows 7, 8 & 8.1 installation discs.

Other operating systems

Our favourite software for setting up a bootable USB drive using .ISO files for other operating systems is Rufus (rufus.akeo.ie). Be sure to have a storage drive large enough for your operating system; 8GB should be enough. Also ensure there’s nothing already on the drive that you might need, as it will be wiped to store the operating system and you’ll lose your existing data.

In Rufus, select your destination USB flash drive from the dropdown menu at the top. If your motherboard was made within the last few years, you can leave Rufus set to using a GPT partition scheme. Tick the box labelled ‘Create a bootable disk using’ and select ‘ISO’ from the dropdown menu. Next, click the disk icon and select the .ISO file you downloaded. Now click ‘Start’ and Rufus will create a bootable flash drive with your operating system of choice.

Step 2 BOOT FROM INSTALLATION MEDIA - Whether you’re installing from a CD/DVD or a flash drive, you’ll need to have your system boot from the correct installation media. Turn on the system and immediately look for an option to access the Boot Menu. This is often F12 on many motherboards, but consult the instruction manual. Select either the USB flash drive or the optical drive, depending on where you want to install from.

If you can’t find an option for the boot menu, you can change the boot priority in the main BIOS itself. This is usually accessed by pressing Del as the system starts up. Press Del repeatedly to be sure of entering the BIOS. Navigate to the storage menu and look for an option to set Boot Priority #1 to whichever storage media you want to install from.

If you use this method, you might need to go back into the BIOS after you’ve installed the operating system to change Boot Priority #1 to the hard disk or SSD where you’ve installed the operating system.

FREE OPERATING SYSTEMS

WINDOWS 10 - If you’re not currently looking to spend money on an operating system, the Technical Preview of Windows 10 is available for free, although no longer directly from Microsoft. Mirrors such as www.windows10update.com exist, but we can’t vouch for the security of ISOs downloaded from these sources.

As this is a technical preview, there may be bugs and other issues ahead of its full release. The good news is that Microsoft has said that anyone who has legitimately purchased Windows 7 or Windows 8.1 will get a free upgrade to Windows 10 within its first year of release, so it might be worth buying Windows 8.1 in the meantime.

ELEMENTARY OS - There are plenty of free Linux distributions available but our current favourite is Elementary OS (www.elementary.io), which is an open-source operating system based on Ubuntu Linux. 

STEAMOS - If you’re looking to create a high-end system purely for gaming, you can install an early version of the SteamOS operating system (store.steampowered.com/steamos/buildyourown). However, bear in mind that you’ll be limited to games from the Steam service that support Linux, unless you want to stream games from another Windows-based PC. For all the latest details read our Valve Steam Machines, SteamOS & Steam Link features, news and release date.

How to ... Troubleshoot PC build problems

So you’ve put everything together and excitedly turn on the PC… but it doesn’t boot up. Don’t panic, though. Go through the following troubleshooting steps and you may find that the solution is surprisingly simple.

PC WON’T POWER ON OR BOOT UP

Check the psu is turned on - This might sound obvious, but it’s happened to the best of us. There’s often a separate power switch on the PSU itself. Make sure this is switched to the ‘on’ position before attempting to boot up the system from the case’s front panel power button. Also check you’ve turned the PC on at the plug, and try a different socket. If you’ve checked everything else, try a different power cable (your kettle may use the same type) or check the fuse in the plug.

Check the front panel connections - If the front panel’s power button isn’t correctly connected to the relevant headers on the motherboard, the power button won’t work. Check you’ve connected the Power connection to the correct header.

Remove Usb devices - Occasionally, motherboards will refuse to boot if devices are connected to specific USB ports. Try disconnecting any connected USB devices or peripherals, such as a keyboard and mouse, and try booting up the system again. If it boots correctly, it will ask you to connect a keyboard and mouse. Do so, but this time try a different USB port.

Check components are seated correctly - Look at the motherboard and check that all the individual components are correctly seated in their slots. Start with the memory. Improperly seated memory is often a cause of a boot failure. If you have multiple sticks of RAM, try installing only one at a time to isolate if any of the modules are faulty. If that doesn’t solve the problem, check the processor and graphics card, if you have one installed.

Check the power cables - Make sure the power cables are connected to all the components correctly. You might have missed the secondary four- or eight-pin power connector to the motherboard, for example. If you’ve installed a graphics card, make sure it has the necessary power cables from the PSU. Any SSDs or hard disks will also need separate power connections.

Listen for the beeps - If the components such as processor fan and graphics card are powering on but the system won’t POST (power-on self-test), the motherboard might provide an error code beep if you have the case’s built-in speaker connected to the header. Look through the instruction manual for your motherboard or do a search online to see what the different beeps mean. This will help you diagnose any problems. Some motherboards may also have a small LCD display that can display error codes making the task even easier.

NO IMAGE ON MONITOR

Check the connection - Make sure the display cable is correctly connected to both the PC and the display. If you’re using DVI or VGA (D-sub), be sure to screw in the connectors so they don’t come loose. If you’re using a dedicated graphics card, make sure the cable is connected to the graphics card and not the integrated graphics output on the motherboard. You may need to change settings in the BIOS to ensure your PC is using the right outputs; you can do this in the BIOS (see ‘Boot priority’, below).

Check the display input - If your display has more than one input, make sure it’s set to display the right one. This will be whichever connection is used on the display itself, so if you’ve used a DVI-HDMI cable and you’ve connected to the HDMI port, set it to HDMI. Do the opposite if the cable is reversed.

OPERATING SYSTEM WON’T LOAD

Boot priority - Your BIOS might be set to boot from a secondary storage disk, USB flash drive or optical disc rather than your system disk, which has the operating system installed on it. You’ll need to change the boot priority so that the PC boots the system disk by default by going into the BIOS.

You can usually enter the BIOS by booting up the system and pressing Del repeatedly. Consult your motherboard’s manual if this doesn’t work. Once in the BIOS, look for a menu referring to the storage disks. You’ll want to change the boot priority order so that the system disk is Boot Priority #1, meaning that the PC will use this storage device first.

Operating system isn’t installed - If you’ve forgotten to install the operating system, or it hasn’t installed correctly, then follow the instructions on installing an operating system, opposite.