PC buyers have never had it so good. It is hard to find a home PC that will not do a decent job of running Microsoft Office and browsing the web, no matter how little you pay. However, buying purely on price can be a recipe for disaster. In the long run, it is better to go for a machine that has been well put together out of quality components, with a specification high enough to last a few years.
There is a myth that all PCs are the same. They are not. What is true is that it can be hard to tell a good PC from a bad one unless you test-drive it for a few weeks. Since you cannot do that, concentrate on getting good components in a machine from a name-brand supplier such as Dan, Dell, Gateway, Hewlett-Packard, or IBM. (This is not a complete list.)
In the UK, Compaq and Dell are by far the market leaders, according to Gartner Dataquest figures for this year's third quarter. Both companies shipped more than 260,000 PCs, and each took 17% of the market.
Hewlett-Packard was in third place with 7%, selling 112,000 of the more than 1.5 million personal computers sold here.
Processor
The processor is the "engine" that runs the PC, so you might think it the most important element in buying one. It isn't. Basically, anything with a speed of 500MHz or (preferably) more will do. Intel Celeron chips are a good choice for budget buyers, but the Pentium III is the best mainstream choice.
Even then, it is not worth paying much of a premium for anything faster than about 733MHz unless you need a high-end machine to run games. If that is the case, you might consider an AMD Athlon processor or even the new Intel Pentium 4.
Memory
If your budget means choosing between a faster processor and more memory, go for more memory. For running programs, today's minimum is 64 megabytes, but 128MB is better, and 256MB is common for high-end users. Make sure the PC has an empty slot to which you can add an extra memory module later.
But "main memory" is not the whole story. It also helps to have lots of "cache Ram" and "video Ram" (VRam).
Level 2 (L2) cache memory is where the PC stores instructions before they are fed to the processor, and it has a critical effect on performance. Video Ram (VRam) is where the screen image is stored, and more graphics memory means you can have more pixels on the screen (higher resolution) in more colours. Graphics cards with 8MB or 16MB are available in low-end PCs, but 32MB is now common, and a few high-end users have 64MB.
Some PCs use part of main memory as graphics memory. This is cheaper but limits performance. It is a very bad idea in a PC that may be used for games.
Graphics and sound
Nowadays, even business PCs have graphics and sound facilities. In low-end machines, these will be integrated on to the main system board.
You get more power for more money by having separate sound and graphics cards that fit into slots on the motherboard. Sound cards usually fit into a PCI (peripheral component interconnect) slot and graphics cards into a 2x or 4x AGP (accelerated graphics port), so don't buy a PC without an AGP slot.
Graphics cards usually have chips to speed up Windows graphics, particularly 3D images. These provide a faster and more responsive system, which is particularly important for games players.
Extra sound and graphics facilities are of limited use unless software houses support them. Home users should therefore lean towards one of the Creative Labs SoundBlaster series and, for gamers, either an nVidia GeForce 2 or 3Dfx Voodoo graphics card, though there are many options. If you are going to splash out on better sound, it makes sense to go for a decent pair of speakers and a subwoofer as well.
Disk drives
A PC should have at least three drives - five or six are not unusual. The basics are a 3.5in floppy, a hard drive, and a CD-rom. The floppy is useful for file transfer and backing up small files, and adds little to the cost of a PC.
The hard drive is used for storing the operating system and other programs, so the bigger the better. Today, 10 gigabytes is average, and 15GB or 30GB is common. High-end machines pack up to 60GB. Cheap systems may only have 6GB or 7.5GB drives, but these are fine for most people. However, if you want to run lots of 3D games, edit videos or collect MP3 files, go for the biggest hard drive you can afford.
The third essential is a CD-rom drive, which is needed for loading software and running encyclopedias such as Microsoft Encarta. Most people will want to upgrade this either to a DVD, which can play movies, or a CD-RW read/write drive, which can take back-ups or, for example, create picture or audio CDs.
It is now possible to get "combo" drives, such as Toshiba's CD-R1002 and Samsung's SM-304B, which read DVDs and also write CDs. However, these are not that much cheaper than two separate drives, and you lose any ability to make disc-to-disc copies. CD-rom drives tend to be sold on speed, but there does not seem to be any practical advantage to having drives that are faster than x16 or even x12.
Some people may also want a fifth drive, usually a high- capacity floppy such as a 250MB Iomega Zip drive.
Expansion
One reason for buying a PC is that it can easily be customised and expanded: you can add TV and radio tuners, video capture cards, network cards, tape drives, modems, printers, scanners, cameras, music keyboards and other things.
But expansion depends on having empty slots and drive bays inside the case and external communications ports for connecting peripherals.
I would not feel comfortable buying a PC that did not have at least two free PCI slots and two empty 5.25in drive bays.
Traditionally, PCs have been provided with a number of dedicated ports (sockets) for the keyboard, mouse, modem (a serial port) and printer, but USB (Universal Serial Bus) ports are slowly replacing them.
I think it is best to go for a "legacy free" PC with as many USB ports as possible. Unfortunately many PCs have only two, which can be expanded by adding hubs. Five is better.
Cases
Buy the biggest case you can bear. Small cases look less threatening and are easier to hide, but tower cases have many advantages. First, they provide room for expansion, and it is far easier to handle fiddly components and the spaghetti of internal wiring in a big case than a small one.
Second, big cases tend to run cooler than small ones, and heat is the enemy of stability and reliability.
PC manufacturers are keen to sell PCs in colourful, curvy cases, but try to avoid becoming a fashion victim. Make sure the case will accept cheap off-the-shelf components such as standard CD and DVD drives, and full-height expansion cards.
Keyboard and screen
Cheap PCs usually come with poor keyboards and fuzzy screens, and mid-range PCs are not always much better. This is a pity because the keyboard and screen are how you interact with the system.
However, most name-brand suppliers offer better screens for some extra cost. Aim for a refresh rate of 75MHz or more at the screen resolution you plan to use: probably 800 x 600 on a 15in screen, or 1,024 x 768 on a 17in model. A low refresh rate creates a disturbing flicker.
There are lots of good monitors available from firms such as Iiyama, NEC, Mitsubishi and Philips.
It is an advantage to have a big screen, because you can see more applications at the same time. Some PCs still come with 15in screens because they are cheap, but it is always worth upgrading to 17in. However, 21in screens tend to be too large and too expensive for home use, and 19in screens may not be a cost-effective compromise.
Many companies also offer flat LCD screens, which take up less room and generate less heat, but they are still much too expensive for the mass market.
Which Windows?
Most PCs come preloaded with Microsoft Windows, but there is a choice of versions. Windows Me (Millennium edition) is the latest, and has been designed for home users. However, it is slower than Windows 98SE (Second edition). Whichever you choose, make sure you also get a Windows CD-rom.
Windows 2000 - a version of Windows NT (New Technology) - is more advanced and works with multiple processors. It is the best choice for business, but a bit too unforgiving for home users.
If possible, buy a Windows 98SE/Me PC that is also offered with Windows 2000 and preferably Unix (eg Linux). Manufacturers can get away with supplying flaky hardware for Windows 98SE/Me, and blaming Microsoft when it crashes. Windows 2000 and Linux generally don't crash, and this exposes hardware flaws.
Bundles
Manufacturers are keen to keep their average selling price as high as possible, and often throw in "free" software and peripherals rather than reduce it. But if these are not items you would buy separately, then you may not get much benefit from them. Free software has no value if you don't use it.
Still, some worthwhile programs may be available free or for a small extra fee. Look for the Microsoft Works suite, Encarta or a similar encyclopedia, and games.
Where to buy?
For most people, the choice is between retail and mail order, which includes telephone sales. Usually mail order offers a better deal, because the direct supplier does not have to buy parts and build PCs weeks or months before it gets your money (this is significant when the cost of computer parts falls every month), and because it cuts out the retailers' profit margin.
However, retailers can offer competitive deals by buying large volumes and slashing margins - Tesco has done this in previous years - and by cutting prices to clear aging stock.
Many firms offer extra information, special deals and clearance bargains on their websites, so check the main suppliers and firms such as www.action.com and Jungle.com.
The drawbacks with mail order/telephone sales are that you cannot see the machine before you buy it, and if it goes wrong, it may be awkward to return it. But you can cover yourself by keeping a record of who you talk to, and what you agree, and by paying by credit card.
You could also consider buying from a mail order supplier with shops or a showroom within driving distance.
If you want something in time for Christmas, you need to act as soon as possible. If not, well, prices will be even lower in February.
