Home PCs still have their place in the sun, thanks to falling prices and ease of upgradeability.
Desktops specs (and prices) vary widely, with the personal PC market divided into three camps: budget systems for everyday tasks such as word processing and e-mailing; media centre PCs and top-of-the-line machines for playing the latest 3D games or editing digital video.
If space is a constraint, the best bet is a small-form-factor (SFF) PC like the one from Shuttle, featured on this page. While they come with a variety of options, upgrades are often limited like the all-in-one systems, thanks to the already built in power supplies and motherboards.
An alternative would be to purchase a Mini-ITX or Micro-ATX compatible case, that should allow you to update the whole system when it's required. All three solutions can also be decent media centres, if you haven't already got your heart set on a dedicated media centre case from the likes of Silverstone, Zalman Alutek or Thermaltake. Take in mind none of these will offer a huge amount of room for hard drives (most will only fit two maximum), so you may want to keep a file server somewhere else in the house and stream to your media box.
For more room for expansion, stick to tower cases. Full tower cases are usually reserved for hardcore gamers, tweakers and system admins, but they have another benefit -- the larger case means there's more room inside, making it easier to work with.
Make sure you get a PC with at least a 500W power supply. When components are not fed power satisfactorily, the reliability of a machine can become flaky.
Always a tricky one -- if you're not buying a complete system off the shelf, you have to get one of these to plug everything else into. The first choice you'll need to make is whether you'll be buying an AMD or Intel CPU, as both need different motherboards. If you're looking into the Intel side, you'll want a board that supports Socket 775; for AMD, it's socket AM2+. Make sure to pay attention to what other components you want in your machine, and check that your chosen motherboard has all the slots available to plug the bits into. Motherboard configurations are all different to suit many different needs, from the tiny Mini-ITX for basic computing, to the standard board, to enthusiast ATX boards with all the bells and whistles. Good known brands are Gigabyte, ASUS, MSI, DFI, Abit.
The basic port connections in a desktop should include USB 2.0 (at least six or eight), FireWire and Gigabit Ethernet. A DVI port is necessary for connecting to a digital LCD screen (usually from a dedicated graphics card), but for sound these days onboard is just fine, although audiophiles will want something like a Creative Sound Blaster X-Fi. Either way, ensure that the soundcard comes with a S/PDIF connector when pairing with a set of digital speakers.
Most of the desktop PCs in the market today are powered by either an Intel Core 2 Duo or AMD Athlon 64 X2 processor. For most users, the rule of thumb when choosing a processor is to go for those which are one to three notches down from the top end as you'll get decent speed and good value for money. MHz and GHz ratings don't matter as much as they once did either, and model numbers have been introduced to make things even more confusing -- so make sure to research the performance of the CPUs you're looking at purchasing.
Desktops running Windows XP or Windows Vista should be equipped with at least 2GB of DDR2 RAM for today's applications, and for future proofing. While DDR3 is slowly coming in, it is prohibitively expensive.
It's generally a good idea to buy RAM sticks in pairs (and in fact, most are bundled as such these days), as they can be used in tandem to increase memory bandwidth.
While you can get crazy sticks with their own heatsinks like the ones on the left, most people should be happy with the plain 800MHz variety supported by DDR2 motherboards on the market, and they're much cheaper too!
Integrated graphics, which shares memory with the system RAM, is generally sufficient for those with basic computing needs such as word processing and e-mail. However with the advent of Vista and increasing graphics needs, your best bet is to go with a dedicated video card, which typically comes with onboard video memory ranging from 256MB to 1GB. For most people's uses, a card with 512MB will be enough, although it's important to note that more memory doesn't necessarily equate to higher performance.
The most common cards on the market these days are NVIDIA's GeForce cards, and AMD's Radeons, although these may be branded under another company's name such as ASUS, Sapphire, Sparkle, Galaxy, EVGA and so forth. While graphics cards can cost over AU$1,000, as a general rule of thumb cards in the AU$300-$500 bracket will cover most people's needs for gaming. The rest of us will get away with something a little cheaper!
The smallest hard drive you can find on desktop PCs today is 160GB, though you will more likely find 250GB and 500GB drives as the norm, which is more than sufficient for the average user. Hard drives over 160GB are usually for those who keep lots of MP3s and movies on their computers or who fiddle around with multimedia applications.
Don't forget that only having one hard drive can be a weak point -- if you lose the hard drive, you lose everything on it. You could invest in an external drive to backup all your sensitive data. Be sensible though -- moving data off your PC to the external drive is NOT backing up. If the external drive fails, you've still lost the data. Simply copy the files across, leaving them both on the PC and the external drive, that way if one fails, you'll have the other.
The ideal set-up should include a DVD+-RW drive for reading and writing discs and a multiformat DVD writer for backups. They're also very cheap these days, going for around AU$50.
Blu-ray and HD-DVD readers and writers are starting to come into the market, however adoption isn't high enough yet to warrant buying them, and they still haven't come down into the affordable bracket.
Widescreen monitors have well and truly taken over, with 19-inch becoming the normal screen size, offering a native resolution of 1,440x900. What you may not know is that 22-inch screens (offering a native resolution of 1,680x1,050) are very affordable these days, hovering around the AU$450 mark.
For those with a lot more money to spend, you can bump up to 24-inch (1,920x1,200) and even 30-inch (2,560x1,200) monitors, although these tend to stay in the realm of gamers, enthusiasts, graphic artists, video editors and architects.
Other useful features
Some PC manufacturers include noteworthy features such as onboard flash memory card readers, TV tuner cards and even wireless LAN in their desktops.
Like notebooks, desktop PCs typically offer a one year warranty. Be sure to look out for onsite support, else you'll be lugging your system to the service centre every time it breaks down. Upgrading the warranty coverage is usually recommended only for higher-end systems. If you've built your own PC, you'll be relying on the warranty of the individual components, which can range from one year to three years.