Choosing the right components

Features James Hunt Jan 2, 2013

You want to build a PC, but how do you start choosing the right components? This guide helps you pick them out

Building your own PC is no mean feat. Whether you’re selecting and assembling the components with your own two hands, choosing them from an online system-building wizard, or even looking at an off-the-shelf system to customise, you’ll have to decide what components you want inside it. That means knowing which ones you want to prioritise and which ones you’re willing to compromise on. You have to think about every component, whether it’s big or small, cheap or expensive, familiar or unfamiliar.

If you select the wrong piece of hardware, it isn’t always easily corrected. One wrong decision can impact another, and it could mean you end up with a system that doesn’t do what you want or a wallet too empty to buy the things you need. Whether you’re after high-end power, mid-range economy or entry-level cheapness, this guide will advise you on what hardware to choose and why. We may not be able to make building a PC easy, but we can at least make it easier!

What type of system do I want?

Before you choose any components, you need to decide what kind of system you’re hoping to have built when the final piece is slotted into place. Just as you wouldn’t buy the same car to journey across the desert as you would to drive to the shops and back, computer systems are built to fulfil a specific end role depending on what they’re going to be used for. That’s one of the best reasons to give yourself a say in the process in the first place: you can ensure that your specific needs get accommodated. 

Here, we’ve narrowed the wide range of potential systems down into five common categories of PC. Pick whichever is closest to the one you want, and that’ll help you gauge the importance of various components and guide your choices.

Gaming PC

In the majority of cases, computer games are by far the most complicated pieces of software that any system ever runs. They rely on intensive processor operations, specialised hardware and cutting-edge technology to perform at their best, the upshot of which is that they’re both sensitive and expensive. You can’t afford to cut corners, because almost any attempt at a substantial saving will result in an instant bottleneck.

Admittedly, you can turn a half-decent workstation into a gaming-capable machine simply by adding a graphics card, but there’s a difference between ‘capable’ and ‘impressive’. The best PCs outperform current-generation consoles by a spectacular margin, but beware, because that goes double for their effect on your bank account.

Silent PC

As the name suggests, silent PCs are built to minimise the amount of noise they make. They’re not usually completely noise-free, but you can get pretty close if you maintain a heavy focus on cooling and component efficiency. More than any other type of system, this means paying through the nose for specialist hardware, and there’s no way to build a ‘budget’ silent PC. However, when you hit that power button and you don’t hear anything except the click of a switch, we have to admit that it’ll all seem worth it.

Workstation PC

Workstations are the type of system most of us will be familiar with, whether from work, school or the shelves of our local PC retailer. They tend to be mid-price, mid-power, and multi-purpose. Most are capable of running simple games and applications, but they also twist to accommodate almost any need, even if they struggle with certain intensive tasks. When building a workstation, the emphasis is on balancing your budget and finding the best value components without spending more than you need. And if you’re after something cheap or entry-level, this is the category you’re aiming for.

Media centre/home theatre

Media centres are designed to act as entertainment hubs, which means your component choices tend to focus on expanding the capabilities of the system, rather than improving its performance. At the same time, you don’t want a computer that can’t keep up with streaming video or drowns out the TV with fan noise while you’re trying to watch it. It’s easy to shave money off a media centre’s PC budget by shopping around for individual components, but don’t cut back too far!

Compact PC

In a market when paper-thin laptops and pocket-sized tablets are all the rage, it’s no surprise that you might want to reduce your PC’s physical footprint too. When building a compact PC, it’s best to start with the case and work your way inwards. You will have to trade off power against size, because small and ‘low profile’ components can be slightly more expensive than most - but compact PCs also resist packing in the sort of extraneous features that most systems tempt you with. Be wary of cheap cooling systems, because the lack of ventilation and proximity of hardware pieces to one another means spending less in that area is a bad idea.

What components should I buy?

Now you know what sort of PC you’re aiming for, you can begin selecting components. Trying to put together a system can seem like the world’s most expensive jigsaw puzzle at times, but take it one step at a time and you’ll eventually find that it’s not that difficult after all. 

To help you figure out what to get and why, in this section we’ll tell you what each piece of hardware is used for, why it matters, and crucially, how interested you should be in it depending on what type of system you’re aiming for. We’ve arranged the components in a loose order of importance, starting with the most essential, gradually giving way to the most optional or specialist pieces.

CPU/ Processor

Prioritise for: gaming and media centre systems

The processor is a good place to start when you’re selecting components for your PC. Not only does it determine what type of motherboard you buy (and thus impact the rest of the system), it determines the overall speed and power of your machine. It’s a good idea to make the purchase of a good CPU the focus of your budget, because the more you compromise, the more your entire system slows down.

Those building performance-oriented PCs should go directly to Intel’s Core line, whether that means a Sandy Bridge or Ivy Bridge platform. Core i7 chips are a good idea for gaming PCs, but media centres and high-end workstations should be able to manage their workload with a Core i5. Core i3’s are best reserved for mid-level workstations or budget systems where you want to leave a little room for upgrades. Intel Pentium CPUs, by comparison, are entry-level and low-power chips best used in budget, silent and compact systems.

In terms of what to avoid, we recommend you don’t exceed a Core i5 unless you expect to do some heavy-duty processing (be that gaming, media editing or coding) and stay away from AMD’s line altogether right now. These chips run hotter, benchmark slower and cost more than comparable Intel chips, with worse prospects for upgrades.


Prioritise for: gaming and compact systems

Once you know what processor you want, you have to pick a motherboard. First, make sure it has the right socket for your preferred chip, which, if you’re following our advice, will probably mean a Sandy or Ivy Bridge board with an LGA-1155 socket. You want an ATX-sized board, unless you’re building a compact PC, in which case go for a smaller iteration, such as mini- or micro-ATX.

Perhaps the biggest question you have to answer when selecting a motherboard is whether you get on-board graphics or not. If you’re planning to install a graphics card, you can definitely skip on-board graphics. If you’re not sure, be aware that on-board graphics chips are more than adequate for most systems, and even capable of doing some light 3D gaming if you have a sufficiently good processor.

Motherboard brands to look out for include Gigabyte, Asus and MSI, but all boards are built on the same reference chipsets, so don’t expect capabilities or performance to vary massively. Features like built-in wi-fi or on-board SSD storage are often attractive, but remember that it’s easy to add these features yourself later on. This doesn’t just save you money: it lets you make a more specific decision over what hardware you end up with. Only pay for extra on-board features if you’re building a compact system, because they naturally benefit from incorporating as many features as possible into one of the few essential components.


Prioritise for: all systems

There’s a fundamental truth about computers, and that’s that you can almost never have too much RAM. Like processors, the ideal course of action is to allocate as much budget as possible and get the most you can. However, unlike processors, RAM is so cheap that it hardly impacts the price by comparison.

If you’re building a PC today, 2GB is considered low-end (and only just enough to run Windows 7 or 8 in 64-bit mode), 4GB is considered up-to-date, and 8GB or higher should future-proof you for years to come. Don’t buy much more than that, though, because only specialist/professional applications will actually be able to take advantage of such an amount.

RAM is useful to all types of system. Gaming machines need it to hold large amounts of data, lowering access times and improving game speeds. Workstations need it to juggle several large applications simultaneously while multi-tasking (think office suites and web browsers). Media centres need it to decode and play video smoothly. And silent PCs need it to reduce disk caching and processing. There’s no type of system that won’t benefit from having more RAM than it needs.

Don’t go mad, though. Performance enthusiasts will want to get hold of expensive high-speed/low-latency ‘gaming’ RAM, and compact systems need special low-profile (reduced height) modules. In most cases, though, you’re fine with unbranded or generic RAM. Just make sure you test it for errors when it arrives. If it’s faulty, you should get a free replacement.


Prioritise for: gaming, silent and compact systems

Once you’ve purchased the previous components, you essentially have a PC built. Now you just need a place to store it. If you’re building a workstation or media centre PC, feel free to go for whichever bog-standard ATX case saves you the most money (media centres are usually ‘desktop’ cases, which fit easily in sideboards and drawers, workstations tend to be towers). If you’re building a gaming, silent or compact system, though, you’ll need to take more care with your choice.

Gaming systems need cases with good airflow and gamer-friendly features, such as side windows, hot-swappable drive bays, screw-free fittings and room for additional fans. You can easily spend several hundred pounds on a gaming case, but don’t lose sight of reality: beyond a certain point you’re paying for unnecessary flash, and a case’s impact on performance is only ever tangible at the absolute top end. You’re only really paying for convenience and aesthetics.
Silent systems are more dependent on a case having passive cooling features such as vents, grilles and heat chambers, because you want as little active cooling as possible. You’ll have no choice but to pay a fair amount, if only to avoid having to install an extra fan.

Lastly, compact PCs are defined by their case. Again, you want as many cooling features as possible, because cramped systems get hot fast. The bad news is that even though you get less case, you still have to pay similar prices as you would for full-size ones!

Storage media

Prioritise for: gaming, silent and media centre systems

You have two choices when it comes to storage: cheap, high-capacity mechanical hard disk drives (HDDs) or fast, low-power, solid-state drives (SSDs). If you’re building a workstation, you can pick up a 1TB HDD for a relatively low price, which should be more than enough space to last the lifetime of the system. Compact PC buyers should look for laptop-style 2.5” HDDs, which are slightly more expensive but necessary to save space.

However, if you’re running a gaming or silent system, you want to make sure you choose an SSD because of their fast access speeds. Gamers will find that they eliminate the data-access bottlenecks that can seriously impair frame rates. Silent PC owners need to rely on their lack of noise and heat compared to HDDs. Both, however, will have to sacrifice capacity at enormous cost: 1TB SSDs don’t even exist commercially right now, but if they did they’d cost almost ten times what a 1TB HDD does.

Media centre builders are advised to go for a fast HDD, which combines the benefits of large, media-friendly capacity with fast, streaming-friendly access speeds. Look for drives that do 10,000rpm at least (standard drives do 7,200rpm). Finally, all users should avoid hybrid SSD/HDD drives. They’re supposed to be the best of both worlds, but in reality they bring the inconveniences of both as well.

Brand names to watch out for include Seagate and Western Digital for HDDs, and Crucial, Kingston, Samsung and OCZ for SSDs.

Graphics chipsets

Prioritise for: gaming systems

Thanks to the generally high quality of the graphics chipsets found on modern motherboards, most systems don’t need a separate graphics card at all. However, if your motherboard doesn’t have a graphics chip or if you want to play things in 3D without resorting to minimum detail settings, you’ll need a separate graphics card.

Graphics cards are power-hungry and expensive. This is because they contain secondary CPUs designed to process nothing but the 3D visuals and pixel-transforming effects found in modern games. The good news is that even a mediocre graphics card can turn a PC of almost any stripe into a gaming-capable machine, since it takes the heavy lifting off the CPU. The bad news is that if you want a good or recent one, they get costly very quickly.

Those building a high-end gaming PC can expect to spend at least as much on a graphics card as they did on the system’s CPU, if not more. The absolute top-end machines run two graphics card using an SLI or CrossFireX configuration, but you’ll need huge amounts of cash. You get impressive performance, but it’s an easy way to see a grand disappear in seconds.

Although enthusiasts and brand fanatics might get upset at us saying it, most users will find that there’s no huge difference between AMD’s Radeon and NVidia’s GeForce lines in terms of price and performance. Unless you’re counting frames, get whichever one fits your budget.

Power supplies (PSUs)

Prioritise for: gaming and silent systems

Although most systems can get away with a generic PSU (400-500W capacity should more than suffice) there are some machines that require you to pay special attention to which PSU you select.

Silent systems, for example, need precision-engineered silent PSUs. The power supply’s cooling fan is a major source of noise in any PC, and that means if you want your system to be quiet, you need to get one that runs cool, has a high efficiency rating and ideally a large, slow-moving fan to avoid noise. Brands like Antec and Corsair are worth looking out for, and anything branded ‘quiet’ or ‘silent’ is, of course, a safe bet. Don’t make the mistake of buying a fan-less PSU, though. These still require cooling from an external source, which is less efficient and ultimately noisier.

At the other end of the spectrum, gaming systems need high-capacity PSUs to support their greater-than-average power needs. Graphics cards and high-speed processors draw a lot of power, and the systems run hot, so don’t even consider a PSU at less than 500W. It’s more likely you’ll need a 650W or even 700W unit. Use an online component calculator to check your system’s likely power draw, and then buy a PSU that has a couple of hundred watts more just to allow for heat loss inefficiencies and future wear. If you buy a PSU that fits your power specs exactly, it’ll probably die quite fast, assuming it’s ever capable of working at all!

Extras to consider

Putting together a PC doesn’t just mean slapping together the minimum number of components. It means taking care to craft one specific to your needs. All of these parts are technically optional, but depending on what type of system you’re building, you may need to consider them. It’s safe to say you’ll want to have some, if not all of them, so go through the list and decide for yourself how important they are to you.

CPU coolers

Prioritise for: gaming and silent systems

Any retail processor should come with a CPU cooling fan that will help to keep it running at a safe, non-damaging temperature. If you’re planning to tax your system to the extreme, though, or want a PC that doesn’t contain a noisy fan, you should look into buying a more sophisticated device.

Those building gaming PCs should look for combination heatsink/fan assemblies that utilise larger fans and highly conductive heat pipes to cope with the higher temperatures a stressed-out gaming CPU is likely to run at. They won’t just extend the life of a taxed CPU, they’ll also allow it to run faster by keeping its temperate at lower levels.

Silent PC builders, meanwhile, should be aiming to install a liquid-cooling system, which combines liquid coolant with larger, slower (and therefore quieter) fans. Some need no fans at all, making them practically noiseless!

Brands to pay extra for include Antec, Zalman and Corsair, but don’t worry too much, since any third-party cooler is going to be an improvement over the one that comes in your processor box.

Sound card

Prioritise for: gaming and media centre systems

The on-board sound chipset included on most motherboards is enough to do the basics, such as play audio from MP3s and videos, record from microphone and auxiliary inputs, and support a standard stereo or 2.1 speaker system. If, however, you’re looking for anything more advanced, you’ll probably want to add a sound card into your setup.

Sound cards add extra effects and processing capabilities, take the audio processing burden off the main CPU, and allow you to add additional IO capabilities, such as optical or digital formats, which can lower interference and improve the quality of your computer’s audio.

Although not an essential component in gaming systems, they can prove useful if you have extra speakers or want to free up your processor as much as possible. Those building a media centre, however, will want the extra capabilities a good sound card offers: things like Dolby surround sound and clearer, more powerful amplifiers.

Despite their long association with the technology, try to avoid Creative cards, because they’re currently in a slump and beset with technical errors. If you want high-end performance, look for something from Asus’s Xonar line instead.

Wireless adaptor

Prioritise for: Most systems

Network capabilities are an essential feature of any current-generation PC, but that’s not to say you need a wireless card. Motherboards usually contain on-board network controllers (often gigabit Ethernet), but using an Ethernet connection means you may have to trail cables around the house or office to reach the router or modem. Wireless adaptors are fast, convenient and, best of all, inexpensive. You can pick up a wireless USB dongle for as little as £10.
However, wireless dongles can tax a CPU, because they do a lot of processing in software. Almost as cheap (and preferable) is a wireless expansion card, which unburdens the CPU, using its additional hardware, making it a good choice for gaming machines. In all cases, look for D-Link or Asus wireless adapters.

Those building compact PCs may wish to look for motherboards with on-board wireless rather than buy a separate card (in order to save internal space), while those with media centre PCs should seriously consider the reliability and consistency of a wired network. If you’re streaming video to your TV, you don’t want a shaky wireless connection causing trouble because someone switched on a microwave!

Optical drives

Prioritise for: media centre systems

The rise of disc-free portable devices, streaming media and online backup services means that buying a PC without an optical drive is no longer the crazy idea it once was. Even gamers can expect to get most of the games they want to play though download services alone, rather than on DVDs. Physical media, whichever way you look at it, is disappearing from the PC market.

The obvious exception to this rule is for media centre PCs. Whether you’re ripping the contents of existing CDs and DVDs, trying to watch the latest Blu-ray movies without compression, or can’t stand long download times, optical drives offer functionality that you simply can’t replicate using an internet connection alone. Samsung, Lite-On, Pioneer and Sony hardware is all good.

Of course, DVD-rewriter drives are useful for general PC users of any kind and as multi-purpose beasts, workstation PCs might benefit, but if you’re looking to cut corners, start here. It’s easy to add one later on if you need to access a DVD or CD, but you’ll probably find you don’t miss having one at all.

TV tuner

Prioritise for: no systems

TV cards are a cheap and effective way to turn a computer into a part-time television and can prove a worthwhile investment for any workstation system that’s going in an office or bedroom without a separate TV. They’re by no means essential, but they are vastly cheaper than buying a separate TV and, after all, you have the monitor, so why not take advantage of that?

Against expectations, media centres probably don’t need TV cards inside them, That’s because you can’t get TV cards that decode the subscription TV services we have in the UK. It’s unlikely you’re building a media PC purely to watch standard-definition digital TV, and if you have a satellite or cable connection, your separate set-top box is going to handle the heavy lifting. TV tuners are a fun and useful extra, but they’re also the definition of inessential.

If you decide you want one, don’t go for a manufacturer other than Hauppauge, and prioritise PCIe expansion cards over USB hardware. The price may be lower, but they’re flimsy and low quality.


Prioritise for: Gaming and Media Centre systems

Media centre builders will probably already have a reasonably buff home-theatre speaker system in mind, one capable of blasting out the cinema-quality sound that computer websites generally leave to the AV specialist retailers. Gamers, though, should look into getting at least a decent 2.1 system (two speakers, one subwoofer) for added bass and quality, if not some variety of 5.1 surround system. 

People building higher-end systems of any kind should be wary of monitor-integrated or unpowered speakers, because they’ll sound tinny and unimpressive. If you’re planning to listen to music or watch media, we suggest a pair of powered stereo (2.0) speakers at the absolute least.

The speaker market is fairly barren for choice at the moment. Logitech and Creative models comprise the bulk of them, and either is fine, although at the lower end of budgets, Logitech probably has the edge.


Prioritise for: gaming systems

A good monitor can spruce up the appearance of a tired old PC or make a good one look awful. The more you spend on them, then better things get, so it can be difficult to decide on a cut-off point and decide that you can live with a lower resolution or smaller viewing angles.

Gaming PCs, of course, should have the best screens possible. Games look best when run in the native resolution of their target screen, and a 1920x1080 resolution model is the absolute least you should be aiming for.
Again, media centre PCs do need a good screen, but even computer monitors don’t reach the dimensions of a good TV screen, so don’t look on computer websites hoping to find a 50” bargain. You’re unlikely to find anything above 27”.

The best brands are Asus, LG and Samsung, and as a general rule, if you want to save money it makes more sense to lose an inch off the screen’s dimensions rather than go for a lower-priced version at the same size, because if you do that, the drop in quality won’t represent good value.

Input devices

Prioritise for: gaming and workstations

When the time comes to interact with your PC, you need to make sure you have a smooth and enjoyable experience. If you’re building a multi-purpose workstation, good input devices can take the rough edges off, making it quicker to interact with and simpler to perform basic tasks. You’ll be amazed how much a five-button mouse or well-made keyboard can improve your day.

That said, it’s gaming enthusiasts who have the hardest time. If you’re relying on a mouse and keyboard combo to play games, there are all sorts of custom technologies to look out for, such as mechanical switches, backlit key, even interchangeable weights to give you the most comfortable movement. They’re not necessary, but they do make it clear you’re serious about gaming.

In all cases, though, avoid wireless peripherals. There’s no real benefit (except, possibly, to media centre systems that don’t have a desktop in front of them), but there are lots of downsides, including a battery life to worry about and sensor positioning. Cables are low-latency, low-cost and low-maintenance. Don’t throw those benefits away because you think you want the apparent freedom wireless offers - you really don’t.

Generally speaking, home users can’t go wrong with any Microsoft-branded keyboard and mice, but gamers might want to go for specialist gaming brands, such as SteelSeries, Thermaltake and Logitech’s gaming lines.

That’s it!

Now, when it comes to choosing components, hopefully you’ll have a better idea which pieces of hardware to concentrate your budget on, and which you can happily discard. And if you need more help choosing the right components, check out our weekly ‘How To Choose’ series, which covers most pieces of hardware in depth!