In parts one and two of this guide we dealt with procuring hardware and assembling it to form a complete PC.

In part three I’m going to give an overview of what you need to do now to make your machine usable.

Operating Systems.

The first thing you’ll need to do is obtain an Operating System (OS) such as Microsoft Windows or a version of Linux.  The OS is the program on your computer from which all your other programs and files are accessed.  Microsoft Windows is the most popular OS, with the latest version being titles “Windows 7″.

Windows 7 comes in a few different varients, with varying features and options available dependant on the varient.  Most home users will be content in purchasing Windows 7 – Home Premium which offers perhaps the best value for money out of all the varients. For dull details on what each version offers, check out the article on Wikipedia here.

You can buy Windows from a number of online suppliers, including those that were mentioned in part one of this series.

The actual installation procedure for Windows I will leave to the installation guide provided with your copy of Windows, there is little point in me re-writing the information provided to you by Microsoft.

If you do not wish to pay extra for an OS, there is an alternative to Windows known as Linux.  Linux is an “Open Source” OS solution, which means that for personal use it’s completely free.  There are many varients of Linux, but perhaps the easiest to use is Ubuntu Linux which we reviewed here.  You can download Linux from the website of each of the varients, most will also include installation instructions.

Security Software

If your computer is to be connected to the internet then it is imperative that you install some form of security software on your computer to prevent it from getting infected and to protect your personal information.

There are two ways to go about this; there are complete security packages available from specialised security firms, such as Norton and McAfee.  These are paid-for products which offer a decent level of protection from all sorts of online threats, such as viruses, spyware and malware.  If you don’t wish to purchase security software, then there are some free alternatives available online.  These offer a reasonable level of protection but updates are often slower to be released than for the paid for products, which means that your computer may be liable to infection for periods of time between viruses being created and your security package being able to detect them.  Microsoft themselves have released a program called Security Essentials which is free to download and offers reasonable protection against online threats.

It’s important not to install all of these products at once; each of them requires processing power to run and slows down your system slightly, if you install multiple versions then the effect will be amplified and your system will function a lot slower than it could.

If you’re using a Linux OS then security software is a lot less necassary, that’s not to say that Linux is impervious to attack, or that you should let your guide down, but being that Linux is a lot less popular than Windows viruses don’t tend to be written to attack Linux.

Installing Updates

In Windows and Linux, you have the option to enable automatic updates so that the latest security updates and utilities are available to you.  It’s important to make sure that this option is turned on as, combined with a decent security package, it will ensure so far as possible that your computer is protected from the threats of the internet.

Installing additional software.

With both types of Operating System there is a massive catalogue of additional software that you can install in order to increase the functionality of your computer.  For details of some excellent free packages for both Windows and Linux,check out our top ten programs for both here and here.

Once you’ve installed security software, updated your OS and installed additional software you’re ready to begin using your computer for it’s true intents.  Hopefully you’ll experience many years of happiness with your machine without the need to change any of the hardware of software, and even then you will likely be able to perform simple upgrades to both the hardware and software without having to go through the complete process of designing and building a PC again.