Windows XP has a System Information Utility which can be quite useful for diagnostics. To use it, go to Start > Programs > Accessories > System Information. You might also find it under the System Tools sub-menu. The utility will provide details of your hardware, software and other components. You can view changes to your system by using the System History option in the Tools menu. This gives a list of changes such as memory addresses and registry settings. Other diagnostic tools are, too, accessed from this System Information utility.