Building a system is not a small task, and it can also be an expensive one. But it doesn't have to be as hard, or as expensive, as it may first appear - as long as you have a clear idea what you want, and what your priorities are when building.
The key aspects for most people considering a new system will be the budget you have available, how long you intend the computer to last, what you're going to use it for, and whether you have any components you want to, or could, hang on to.
We've also provided a primer for picking the key parts of a system, just in case you want to get to business immediately.
Build to a budget
When you have limited money to spend, building to a budget is your best option. Set yourself a minimum and a maximum you're willing to spend, and if you're planning your entire system around a rigid budget, check out our "Good enough" section, too.
Even if you're flexible with your money, it pays to set a maximum and stick to it. It's remarkably easy to be talked into a little bit extra here and there that you may not need, and that won't add to the overall performance, but will make a serious dent in your wallet.
One tip that I would certainly recommend is to decide how to divide your budget between the components required for a new system. It's affected by the overall budget, but see her suggestions for a low, mid-range and high-end system below.
When factoring in to your budget, make allowance for the components you absolutely need, and those that are optional extras (as well as which ones can be readily upgraded later). What you'll need is a processor, RAM, hard disk drive or SSD for storage, a motherboard and case.
You may need a power supply - they often come included with a case, which provides good value. If you're building a system with high power needs, it may be worth allocating budget to buy one separately. Other components we've considered are peripherals.
You may need an optical drive, such as a DVD writer, but if you've had a previous system, you may be able to scavenge your old one. Similarly, consider carefully before spending on a new monitor, keyboard and mouse if your old ones are still serving you well. Generally, processing parts such as the graphics card, CPU and RAM will be outdated, and should only be used if suitable.
Also consider re-using your OS, if it's not an OEM version. We recommend 64-bit Windows for new systems, if you can afford it, and Windows 7 has several advantages over Vista in terms of security and managing system resources.
Depending on your needs and how large your budget is, you may be able to get away without needing a dedicated graphics card. If you only use your system for the basics, for example, the integrated graphics processor that comes with many budget and mid-range motherboards should be adequate. It's a relatively easy step to upgrade later if you change your mind, or you find your system is sluggish.
It's a good idea to allocate a proportion of your budget to each component, and try to find the best you can for your money. If storage is your key requirement, for example, then you may want to budget a couple of hundred dollars for hard drives.
If on the other hand you're sure you'll have money later and will want to upgrade, then an expensive motherboard may be a good investment, combined with a cheaper processor.
We've given an idea of the kind of proportion a part might take up in a cheap, mid-range and high-end system, but be prepared to be flexible and adapt if you find a good deal.
Build for the future
While building to a budget is great (and an important part of any system building exercise), sometimes you'll want to build a system that you can hand down to other family members after you're done, or turn into a server, so you'll want to know that it will last several years without drama.
While many components have basic 1 year warranties, if you're after a system that will remain fuss-free it's worth looking for parts that have longer warranties. As an example, the Western Digital Velociraptor hard drive has a five year warranty, compared to the 1 year for most standard 7200rpm drives. The cost is commensurately higher, however.
Another key area for a long-term build is the motherboard, which determines the capabilities of your system. It's worth looking for a motherboard with as many bells and whistles as you can - more features included often means more future-proofing.
Right now, for example, an X58 board has true USB 3, as compared to the P55/H55 boards, which have a workaround version. While there were virtually no USB 3 gadgets available at time of writing, it's a certainty that there will be in the next year or two, and it's likely to become the dominant standard quite rapidly.
Also keep an eye out for system bottlenecks - hard drive speed is a limitation at the moment that SSDs help to get around. SATA 6GB/sec is a key change that improves speeds around the system.
Opting for a new motherboard with capabilities in these areas will help reduce the effect of bottlenecks if you upgrade the system later. It's not worth factoring into a system that may only be used for two years, but may be vital for one used past that point.