Should I Disable PreFetch?
In a word... NO! This is the stuff of myth and legend. If you disable the PreFetch facility in Windows, it will cause a NEGATIVE impact on performance for most systems. Commonly used applications will take longer to load because you turned off the caching.
Cleaning the pre-fetch folder is not necessary. Windows manages it automatically, dropping out entries that are old or unused. In addition to making your frequently used programs load slower, it will also INCREASE bootup time because Windows has to re-copy all the page files you "cleaned out".
Everything I have read indicates that the default setting for the Prefetch parameter is optimal for most users. Additionally, the folks from Microsoft say that fiddling with the Prefetch setting in the Registry or the contents of the C:\windows\prefetch or C:\winnt\prefetch folders is COUNTER-productive, and that adding a "/prefetch:1" flag to shortcuts that launch a program will NOT make it load faster. It may even cause a program to crash. Here's a snippet from taken from the Microsoft website:
"Windows XP monitors the files that are used when the computer starts and when you start applications. By monitoring these files, Windows XP can prefetch them. Prefetching data is the process whereby data that is expected to be requested is read ahead into the cache. Prefetching boot files and applications decreases the time needed to start Windows XP and start applications."
Here's another excellent page that gives solid info from actual Microsoft developers and debunks some of the misinformation people are passing around as fact: http://www.edbott.com/weblog/archives/000743.html
Bottom Line: Let the operating system manage the pre-fetch cache -- that is its job. If you want more tips on making Windows run faster, don't miss http://www.askbobrankin.com/make_windows_xp_run_faster.html.
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