Gaming on the PC can be a daunting experience – it's a platform laden with more technobabble than an average episode of Star Trek. It shouldn't be though; with less than ten major components inside each PC it's actually easier to build a gaming rig than an Ikea coffee table. In part one of our Gamer's Guide to the PC we explained what the CPU, motherboard and memory do, while part two focused on the PC's graphics card. It's time to complete our beginner's guide with a look at the other bits and pieces that go into a gaming rig – the sound card, power supply, storage and case.

A quality PSU is a good foundation for a rock solid stable PC.
The Power Supply Unit (PSU)
Continuing the slightly creepy analogy to the human body that we've been using for the entire series, the PC's Power Supply Unit (or PSU) is the PC's heart – pumping the vital juice (electricity) to all of the other organs. Thankfully buying a PSU couldn't be easier. Unless you're a super hardcore overclocker who needs absolutely perfect power to maintain stupidly fast overclocks, the rest of us only need to worry about the PSU's total power output, which is measured in Watts. Each component in your PC draws a certain amount of power, with the GPU asking for the most juice, followed by the CPU. When buying a PSU, check the recommended PSU supply listed on the manufacturer's website; for most PCs a high quality 850W PSU should do the job nicely. If you're packing a dual or triple GPU system expect to pay more for a 1KW or higher PSU. We don't recommend buying a bargain basement PSU, as they can lead to unstable performance for your entire PC. Also, check that it's got the right outputs for your motherboard, graphics cards and SATA devices – thankfully nearly all new PSUs have all of the right plugs, but cheap adaptor cables can be bought for less than $5 to enable older PSUs to work with today's GPUs and SATA drives.

SSDs are extremely fast, but also extremely wallet unfriendly.
Storage: The Long Term Memory
In part one we explained that the system memory or RAM is the short term memory of your computer, but what about the long term memory? Enter the PC's hard disk drive, which is where all of your long-term data is stored. The hard drive contains every application, photo, lolcat video and swimsuit model wallpaper on your PC, and unlike system memory, everything stays in place even when the computer is turned off (your RAM is wiped clean when the PC reboots). Today's drives use a connection called SATA to plug directly into your motherboard, which comes in two variants – SATA 2 and SATA 3. Obviously SATA 3 is the faster type, but you'll need to have SATA 3 ports on your motherboard to make the most of a SATA 3 hard drive.

Until a couple of years ago hard drives were of the mechanical variety – these work much like an old record player, with several records (platters) spinning at stupidly fast speed while a magnetic head reads data off the record. The faster the platters spin, generally the faster your drive will be able to load data, resulting in quicker game and operating system loads. Mechanical drives now offer huge amounts of storage space, regularly breaking the one Terabyte barrier (which is equal to 1024 Gigabytes).

However, a couple of years ago a competitor to mechanical drives arrived in the form of Solid State Drives (SSDs). These use the same memory found in your USB thumbstick, and offered exponentially faster performance – we're talking up to sixty times faster in some circumstances. Games that once took a minute to load now fire up in less than ten seconds, and your PC's boot time can be halved. However, there's a catch – SSDs are much more expensive than mechanical drives. Only the offspring of Bill Gates can afford several Terabytes of SSD storage; for us mere struggling mortals even a 256GB drive is rather expensive. As a result, we recommend a 128GB SSD for your operating system and a few favorite games, along with a 1TB mechanical drive for everything else.

Making things a little more complex is a technique called RAID, where multiple drives can be hooked up to either perform faster, or to automatically back up data. RAID is for more advanced users though, so we'll save that topic for a little later down the track.

The final piece of storage technology inside the PC is the optical drive, which is used to load disk-based applications into the PC, as well as to burn data to an external disk. There are two options here; a cheap DVD burner, which can both read and write to DVDs, or a Blu-ray drive, which is only necessary if you want your PC to double as a home theatre box or you need to back up stupidly large amounts of data on stupidly expensive burnable Blu-ray disks. If you're thinking of the latter, we'd suggest an external USB 3 hard drive as a much cheaper method of backing up data.

The humbe soundcard - a must-have for any quality gaming rig.
Soundcards
Many gamers mistakenly believe that the days of soundcards are well and truly over. This is because their iPod-damaged ears have only ever listened to the integrated soundcards that most motherboards now include. However, we absolutely disagree; if you want your games to sound the way the developer intended, it's well worth adding in a sound card. After hearing the delights of a dedicated audio card we'd never go back to the crude audio of a motherboard audio chip. The sound card plugs into your motherboard and handles all the audio processing for your PC, in the same way a graphics card handles all your video. It turns out that audio is about a billion times easier to manage than graphics though, so sound cards don't need expensive hardware to do a great job – you can pick a beauty up for less than one hundred dollars. Our current favorite is the ASUS Xonar range, which comes in a variety of flavors (the DX is nice and cheap), though Creative still has a healthy selection of SoundBlaster cards on the market. Soundcards can be attached to your motherboard via two methods – a PCI Express slot or a PCI slot. Check your motherboard to see which is the most convenient method for you, as there really isn't any discernible difference in audio quality between the two.

If you're planning on using PC speakers or regular headphones, any sound card should have the 3 x 2.5mm minijacks on the rear that is necessary to deliver surround sound. However, if you'd like to pump game surround sound to your home theatre amplifier over optical (which is a common option on most amps), you'll need a card that supports Dolby Digital Live, otherwise your games will only play in stereo over the optical out. Again, this is why the ASUS Xonar DX is a favorite here in the GameSpy tech cave.

A nice big ATX case provides plenty of room for your kit.
Get on the case
The final painful analogy you're going to have to endure is the case, which is like your body's skin. Yeah, we told you it was painful. The case is what everything goes into, and if you're building a gaming rig we recommend you go for the roomy ATX size, as this gives your steaming hot silicon plenty of room to breathe. It'll also play nicely with any ATX PSU you buy, and a couple of case fans should help circulate its sweltering innards. If you're looking to build a LAN-box, you might like to try a SFF (Small Form Factor) case, but bear in mind you'll be severely limited in what you can squeeze inside. There's also a healthy new market selling Home Theatre PC cases, which are designed to fit in nicely in your AV rack, but again they don't have quite as much room as a gaming rig demands. When buying a case, make sure you like the way it looks (duh) and the ability to change your heatsink without having to remove the motherboard, courtesy of a heatsink cutaway in the motherboard mount, is a nice-to-have feature. Prices for cases vary anywhere between $50 and $500, depending on how much you value your PC's vanity.

So there you have it – the basics of the PC really aren't that difficult once you've had them explained to you. Now that you know what all the pieces are, it's time to have a go at putting them all together in your first ever D.I.Y. PC build. We'll have a guide on how to do that in the very near future.


Spy Guy says: I find it quite funny when PC boffins rattle on about how complex PC technology is – at the end of the day it's a handful of components that even my gran could put together. Which area of PC tech do you find the most confusing?