Starting from Windows XP, Microsoft has introduced a mechanism called Prefetch, which allows for performance improvement while starting up your system. Prefetch is implemented as a folder under your Windows directory. In case you don’t see the indows directory, you should first allow showing hidden files.

Taken from Microsoft Technet:

By observing successive boots of the system, Windows XP can dynamically determine the code and data needed for the boot and can optimize the placement of these files on the disk. When the computer boots, Windows XP can issue large I/O requests that can be handled efficiently with high throughput. Moreover, the operating system can find opportunities to issue these requests so that they will overlap in time with device detection and initialization. This is done in a way that will not add to the overall boot time. This allows for subsequent processing to occur with the operating system substantially resident in memory, and dramatically decreases the time needed for the system to boot.

The thing with Prefetch, is that it often gets filled with obsolete files, and that hinders its ability to speed up your PC boot.

The solution is to periodically cleanup the Prefetch directory, and here’s how you can do it:

• Click Start 
• Click Run (In case Run is not available as an option in your Start menu, you can make it appear, by following this procedure)
• Type Prefetch
• Click Ctrl+A (select all)
• Right click and select delete
• Close the Prefetch explorer.

Looking for an additional way to increase your PC boot perfroamnce? See here.

[tags] Windows Vista, Vista, Windows tips, Windows Tricks, Windows XP, Prefetch [/tags]