The perfect desktop PC is quiet, but powerful. It's got enough storage space to hold your expansive DVD collection, but it's small enough to tuck inside a cabinet.

It should look good and be ready to tackle any of the latest games, but it shouldn't cost you so much that you can't afford to buy any of them. And another thing...

In fact, the perfect PC means different things to each of us. Search hard enough and you may find a factory-made machine that matches your ideal, at a reasonable price. But if you'd rather not wait for a PC vendor to read your mind, consider building your own.

It sounds pretty daunting, but putting together a PC is a lot easier than you might think. And there are plenty of good reasons to do it.

Do your own troubleshooting

If you've ever had to return a computer for repair, the experience may have encouraged you to think seriously about rolling up your sleeves and doing your own troubleshooting. Lengthy turnaround times and hours spent on hold with customer service are maddening enough. But if your machine is out of warranty – or didn't have a very good warranty to begin with – the cost of getting a part or the entire system replaced could be more than you bargained for.

What's more, building your own system is fun. Technology has become increasingly complex, but PCs are modular and, with our step-by-step guide, you can put together a dream machine that's just right for your needs and budget.

Note, though, that the do-it-yourself process is a double-edged sword. Whether or not you've had positive customer-service experiences in the past, having a single seller to turn to for help if your equipment goes haywire can simplify troubleshooting (and makes replacement parts easier to find). Getting a faulty component replaced on a home-built machine entails working with individual product manufacturers, which can mean extra hassle.

What do you want from your PC?

But, caveats aside, you'll be hard pressed to find a computer that suits your needs better than one you build yourself. The first and most important step in building a PC is to know exactly what you want it to do. The only thing worse than wasting time assembling a sub-par system is spending far more money than you need to. There's little sense in cobbling together a quad-core behemoth that you'll be using only to check email and browse the web.

Once you've identified the functions that you want your PC to perform, decide how much you're willing to spend. A system designed for gaming or video editing will require a larger investment than one intended for nothing more demanding than surfing the web.

The parts lists we've provided for our sample builds reflect what we were trying to achieve – a budget build in the first example; a more entertainment-focused PC in the second. We've also added some suggestions of how you might tweak the basic component list for each to give you more graphics grunt or slicker everyday performance. Only you can decide what you think is a reasonable amount to spend on a graphics card or processor and how much you're prepared to lay down overall.

NEXT PAGE: The parts list

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Parts list: £365 PC

It's not easy to build a PC for £365. No matter how you slice it, you're going to have to make some sacrifices. That said, we were impressed at how much computing power we managed to assemble. Here are the parts we chose for our budget PC build, along with the reasons we picked them. The prices listed here are ones we found at reputable online stores; the numbers may have shifted by the time you read this.

CPU: AMD Athlon II X3 445
£55 inc VAT
At the low end of the price range, AMD's processors provide really good performance for the money. What's more, choosing this CPU enables us to use an affordable motherboard with very good integrated graphics. We found we could pick up the 3GHz edition for £55 at Yoyotech, while the marginally faster 3.1GHz CPU can be found online at sites such as Scan Computers for £60.

CPU cooler
Free
The AMD Athlon processor that we chose comes with a stock CPU-cooling fan, so we didn't have to spend any extra money to get this component.

Motherboard: Biostar TA890GXB
£73 inc VAT
It's vital that the CPU and motherboard are compatible with each other. Having chosen our AMD X3 processor, we looked around for a low-cost motherboard. The Biostar is built on the microATX design and offers AMD's latest chipset, support for the full range of AMD CPUs and HD 4290 graphics (one of the best integrated options available).

RAM: Crucial DDR3 1,333MHz 2 x 1GB
£36 inc VAT
We'd prefer 4GB of RAM, but our budget won't allow it. Crucial makes reliable RAM at a fair price, and this pair of 1GB DDR3 memory modules will get the job done.

Case: AOPen H425B
£35 inc VAT
Since we've chosen a microATX-based motherboard, we want a compact chassis. Prices start around £25, with Taiwanese names such as Foxconn and Lian-Li featuring prominently here – they know how to make solid components to a budget. However, if you feel as though you've skimped enough already, you could pick up a very nice Antec Performance One case for £55. We've chosen a value case from AOPen.

Power supply unit: Cooler Master Elite 460W
£29 inc VAT
The power supply unit (PSU) is a critical part of your computer build, especially if there's to be both a nippy processor and a powerful graphics card generating heat and drawing power. For this low-cost build, we don't need a PSU with an especially high rating. Instead, we need one that's inexpensive and reliable. Cooler Master's 460W model fits the bill.

NEXT PAGE: More parts for our £365 PC

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Graphics: ATI Mobility Radeon HD 4290
Not applicable
In lieu of a graphics card, we're relying on the motherboard's integrated graphics. If you're a gamer, you'll want to invest in a decent standalone graphics card. The cheapest card in our graphics card charts is the £77 Sapphire ATI Radeon HD 5570 with 1GB of video memory. Look for a cheaper, less memory-strewn version of this ATI graphics chip and you'll be all set. A 512MB Powercolor version costs £45 at Lamdatek, for example.

Hard drive: 500GB Seagate Barracuda 7200.12
£28 inc VAT
Hard-disk drives are amazingly inexpensive these days. This 7,200rpm drive from Seagate performs quite well, holds half a terabyte (TB), and can be picked up for less than £30. You can get a 1TB version of the same drive for around £49 online.

DVD drive: Asus DVD-E818A6T
£12 inc VAT
This is an extremely simple and basic DVD-ROM drive. It reads DVDs and CD-ROMs, but it doesn't burn discs – nor does it play Blu-ray Discs. It costs only £12 from sites such as tekheads and ginger6, which is perfect for our tight budget.

Operating system: Windows 7 Home Premium 64bit (OEM version)
£75 inc VAT
Linux costs less, but we want compatibility with mainstream programs. Despite having just 2GB of RAM, we opted for the 64bit version of Windows 7. It offers a slight security edge and provision for future upgradability. To qualify for an original equipment manufacturer (OEM) operating system simply buy your hard drive at the same time as you purchase the OS.

Keyboard: Microsoft Comfort Curve Keyboard 2000
£10 inc VAT
It's easy to splurge nigh-on £80 for a keyboard and mouse. Shopping carefully online, we found this perfectly adequate keyboard for just £10 at Amazon. Given its ergonomic credentials, we were pretty pleased with this attractive, low-cost find.

Mouse: Microsoft Comfort Optical Mouse 1000
£12 inc VAT
Perhaps not such a steal as the keyboard we found to go with it, the £12 Microsoft Comfort Optical 1000 is better than the generic low-cost mice that ship with most budget PCs. And because it's so cheap, it helps us keep our system's overall cost down.

NEXT PAGE: Parts for a £912 PC

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Parts list: £912 PC

CPU: Intel Core i7-875K
£230 inc VAT
This 2.93GHz Intel Core i7 processor has four cores (eight threads) and a 1,333MHz frontside bus. This enables it to deliver plenty of power. And since it's unlocked, it gives overclockers lots of options.

CPU cooler: Akasa AK980 Core i7 CPU Cooler
£16 inc VAT
We've opted for a fairly inexpensive CPU cooler. You can pick up a generic Core i7 processor cooler for around £10. But if you need a quieter fan, or one that can cope with the increased heat generated by an overclocked PC, you'll need to set your sights a little higher – consider Akasa's £37 AK967 Core i7 CPU Cooler.

Motherboard: Asus P7P55 LX
£79 inc VAT
This motherboard offers a fanless design and CrossFireX support that enables you to use two ATI graphics cards. The P7P55 LX supports up to 16GB of RAM and any Core i5 or i7 processor that uses the LGA 1156 socket type.

RAM: OCZ Platinum DDR 1,333MHz 2 x 2GB
£70 inc VAT
We reckon 4GB is enough for any modern home PC, and we'll have two slots open, so we can double our system's memory later by adding another pair of 2GB memory sticks. This high-quality OCZ pairing combines a high clock speed and good value.

Case: Zalman Z7 Plus Black ATX Tower
£43 inc VAT
The Zalman Z7 Plus is a great mid-size tower PC case for the price. It looks good, has thick sides to dampen noise, and includes several 120mm fans to keep things cool.

Power supply unit: Antec EA650 650W
£74 inc VAT
Antec's EarthWatts PSUs are energy-efficient and reasonably priced. We don't really need 650W for the components we've chosen, but it's sensible to build in a little breathing room for future upgrades or overclocking.

Graphics: XFX ATI Radeon HD 5850
£205 inc VAT
This is one of the best graphics cards available for around £200. It's quiet, supports DirectX 11.0 and it can run every modern game, even at high detail levels.

NEXT PAGE: More parts for our £912 PC

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Hard drive: 1TB Seagate Barracuda 7200.12
£49 inc VAT
This drive resembles the excellent Barracuda drive we used in our budget PC. Here, we've doubled the storage capacity to 1TB, but a £39 750GB version is also available. Alternatively, look for improved speed and compromise on capacity by fitting a solid-state disk (SSD) instead. Crucial's 64GB SSD costs a mere £105 – and you can always add in a cheap external drive later on.

Optical drive: Asus DRW-24B1ST
£18 inc VAT
This optical drive is more capable than some. It burns single-and double-layer DVDs as well as CDs. With the exception of Blu-ray support, it does everything you could want from an optical drive. For Blu-ray playback add £40.

Operating system: Windows 7 Home Premium 64bit (OEM version)
£75 inc VAT
We haven't compromised with the operating system for our budget build and we won't here either. To make full use of our 4GB of RAM, we want the 64bit edition of Windows 7.

Keyboard: Microsoft Comfort Curve Keyboard 2000
£10 inc VAT
We were so taken with the budget keyboard we sourced for our low-cost PC build that we're using the same one for our pricier build. Anything else we found of a similar quality was at least twice the price.

Mouse: Logitech MX 518
£43 inc VAT
We want a slightly more luxurious mouse than the one on our budget build. Logitech makes some great PC peripherals and this little rodent fits the bill. Large and comfortable, it tracks smoothly and is sensitive enough to satisfy gamers.

NEXT PAGE: Step-by-step assembly

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Step-by-step assembly

Before you start, get your tools in order. Fortunately, you won't need many.

To open the boxes that components arrive in, keep a box cutter or a sharp knife handy. You'll also need to cut away any cable ties that stand in the way.

Quite a few screws will accompany each of your components, and they may not be interchangeable. Keeping things organised will simplify things. You'll need a Phillips screwdriver to put everything together, so be sure to have one available.

Finally, have a few twist and cable ties on hand. Building a PC can be messy work, with a rat's nest of wires protruding from the PSU and plugged into your components. But besides being annoying while you're mucking about inside the case, tangled wiring can cause components to get hotter than they otherwise would. Tying back cables to keep them out of the way will keep cool air flowing throughout the chassis.

Assembling a PC isn't as hard as you might think. Just clear a couple of hours from your day and find a big, clean space to work in. Below we've listed the nine steps you'll take to assemble your homemade PC. As you'll see, it's not very technical, and doesn't require special tools or skills. For a more detailed demonstration of building a PC, see our short video series at tinyurl.com/dkn7z4.

Once you've built your PC, visit our walkthrough on installing Windows.

Step 1


Install the PSU: Line up the PSU's holes with the mounting space in the case and screw it in.

Step 2

Install the motherboard: Screw the spacers into your case, and then screw the motherboard on to the spacers. Plug the power PSU and case buttons (power, reset) into the motherboard.

NEXT PAGE: Install the CPU

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Step 3

Install the CPU: Gently place the processor in the socket and fold the lever down to lock it in place. Place thermal grease on the CPU if necessary, then snap or screw on the CPU cooler.

Step 4

Mount the CPU cooler: Position the CPU cooler over the mounting holes, adding a dab of thermal paste to the CPU if necessary. Some coolers have snaps and some have screws; either way, tighten it down securely.

NEXT PAGE: Install the RAM

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Step 5

Install the RAM: Line up the notch in the RAM with the slot and press firmly until it snaps into place.

Step 6

Install the hard drive: Screw the hard drive into the mounting brackets (usually in the front of the case). Attach the SATA power cable from the PSU, and the SATA data cable to the motherboard.

NEXT PAGE: Install the optical drive

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Step 7

Install the optical drive: If you have rails, screw the drive on to them and slide it into the case. If not, slide the drive in and screw it into position. Attach the SATA power cable from the PSU and the SATA data cable to the motherboard.

Step 8

Install the graphics card: If you're using integrated graphics, you can skip this step. Push the graphics card firmly down to seat it in the large PCI Express slot closest to the CPU. Then plug in the power connectors from the PSU.

NEXT PAGE: Install the OS

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Step 9

Install the operating system: Attach your keyboard, mouse and monitor, then turn on your PC and put the Windows disc in your optical drive.

The perfect PC: How did we do?

For testing our DIY system, we used the WorldBench 6 processing-speed test. WorldBench 6 gauges real-world system performance using a series of tests based on common applications. We calculate WorldBench 6 scores by timing how long a PC takes to complete the various tasks, and weighing those numbers against the performance of a baseline system.

We then compared the test systems' performance against that of our current Test Centre crop. It's not a completely scientific test – not least because PC vendors don't always leave the CPU clock speed at its default multiplier setting, especially if they're keen to win a recommendation – but it gives a fair idea of how our PC stacks up against one from an assembly line.

Our budget PC vs the competition

When it comes to building a PC on a tight budget, PC manufacturers have a clear advantage. By ordering in bulk and maintaining direct control over their supply chain, they can buy components at lower prices than an individual user shopping for parts online. On the other hand, they have to pay for assembly and make a profit.

Overall, our results weren't bad. On our WorldBench 6 tests, our low-cost system scored 18 points below our current Best Buy PC in the same price category.

Graphics performance was better, but not exceptionally so. We couldn't eke out a playable framerate, regardless of settings, which is normal with integrated graphics.

Limitations in gaming performance aside, our lower-budget machine excels at tackling HD content. The motherboard's integrated graphics chip offers Mpeg2 and H.264 decoding, which helps lighten the load on the CPU. The end result is smooth, stutter-free playback, even at higher resolutions. You'll also have enough power to run multiple displays – an arrangement that's handy for getting work done when you aren't watching your favourite films.

Despite its marginally lower performance, our £365 machine has a few advantages over competing prefab systems. Our chassis isn't much larger than the average, but it can accommodate various components that you may want to introduce later on. Likewise, our motherboard's integrated graphics system leaves PCI slots available for adding a discrete graphics card.

Our budget PC: £365 inc VAT, 108 WorldBench 6 points

Palicomp Core i3 Blast 540-22 USB3: £499 inc VAT, 126 WorldBench 6 points

Chillblast Fusion Assassin: £500 inc VAT, 123 WorldBench 6 points

NEXT PAGE: Our power PC vs the competition

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition

Designing and building your own PC is a great way to get your ideal system for the right price – and it's fun too

Our power PC vs the competition

Whereas our low-cost machine struggled a bit to keep up with its similarly skinflint preassembled peers, its more generously specced sibling had no such trouble. The higher price ceiling allowed us to focus on getting stronger performance, while building a machine that was quiet, user-friendly and reasonably attractive.

Our £912 machine's WorldBench 6 performance was only five points lower than that of our current Best Buy PC in the same price category. Although it didn't quite outrun our chart-toppers, bear in mind that the Core i7-875K processor we used is unlocked and overclocker-friendly.

If you're feeling adventurous, you can easily push the CPU beyond its stock clock speeds and get a little more mileage out of your system. You can obtain even more legroom by upgrading from the inexpensive CPU cooler we selected to something a bit larger. Even if you'd rather not dabble with overclocking, this setup offers performance results that are hard to beat at this price.

Graphics performance was also noteworthy, which will please home PC builders looking to play games. The XFX ATI Radeon HD 5850 turned in 96fps in Unreal Tournament 3 at the game's highest settings (2560x1600 resolution).

As with our budget model, taking the do-it-yourself route enabled us to choose a fairly versatile case. The Zalman Z7 chassis has plenty of bays for future expansion, while muffling much of the racket that the components make.

Our power PC: £912 inc VAT, 138 WorldBench 6 points

Palicomp Core i7 Blitz 930-24 USB3: £999 inc VAT, 143 WorldBench 6 points

Arbico Elite i7-8785 HD: £1,000 inc VAT, 143 WorldBench 6 points

See also: Pictures: 9 ludicrously expensive dream PCs

  1. It's easier than you think
  2. The parts list
  3. More parts for our £365 PC
  4. Parts for a £912 PC
  5. More parts for our £912 PC
  6. Step-by-step assembly
  7. Install the CPU
  8. Install the RAM
  9. Install the optical drive
  10. Install the OS
  11. Our power PC vs the competition