Myth... if you delete the Windows Prefetch folder you will improve performance

There is a Myth that in Windows XP if you delete the Windows Prefetch folder you will improve performance. This is not true. In Reality Every time you delete an application's Prefetch (.PF) file you will cripple that application's load time the next time you go to launch it. This can temporarily increase load times by as much as 100%. For one thing, XP will just re-create the Prefetch (.PF) files anyway; secondly, it trims the files if there's ever more than 128 of them so that it doesn't needlessly consume space. However you do not regain optimal application load times back until after the second time you launch the same application due to the Prefetch (.PF) file being re-created. Prefetch (.PF) files are not a cache and are not preloaded into memory upon windows startup. They are never even accessed until you launch an application. Only one Prefetch (.PF) file per application is created. There is never ANY reason to delete these files. Cleaning the Prefetch folder is actually a temporary self-inflicted unoptimization.

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