Adjust Windows Prefetcher Settings in Regedit

The Windows Prefetcher is a built-in memory management component designed to decrease application launch times and improve system startup performance by caching necessary data into RAM. This guide explains how to access the Windows Registry Editor and configure the system-wide file system prefetcher operating states by modifying the EnablePrefetcher DWORD value to match your performance requirements.

Step-by-Step Guide to Modifying Prefetcher States

  1. Open the Registry Editor Press Windows Key + R to open the Run dialog box, type regedit, and press Enter (or click OK). If prompted by User Account Control (UAC), click Yes to grant administrative permissions.

  2. Navigate to the Prefetcher Key Paste the following path into the address bar at the top of the Registry Editor window and press Enter: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\PrefetchParameters

  3. Locate and Edit EnablePrefetcher In the right-hand pane, find the DWORD (32-bit) value named EnablePrefetcher. Double-click it to open the Edit DWORD Value dialog box.

  4. Change the Value Data Set the Base to Decimal (or Hexadecimal, as the values 0–3 are the same in both), then enter one of the following numeric values into the Value data field:

    • 0: Disabled – Completely disables the file system prefetcher. (Commonly used to reduce write cycles on solid-state drives).
    • 1: Application Prefetching Only – Enables prefetching solely for application launches, ignoring boot files.
    • 2: Boot Prefetching Only – Enables prefetching solely for Windows startup/boot files, ignoring application launches.
    • 3: Entire System Prefetching (Default) – Enables prefetching for both boot files and application launches for maximum performance on standard HDDs.

  5. Save and Restart Click OK to save the changes. Close the Registry Editor and restart your computer for the new prefetcher operating state to take effect.