Virtual Memory and your hard disk drive

Virtual memory or "page file" is a location on your hard disk drive that is built to simulate DRAM. When you begin running low on physical DRAM, you computer automatically begins to move critical DRAM data to your page file. The page file is typically 1.5 times the amount of physical DRAM you have installed in your computer system (so if you have 2GB of DRAM installed in your system, your virtual memory settings would automatically be set to 3GB of space used on your hard disk drive, 4GB of main memory would utilize 6GB of hard disk drive space, etc. This space is reserved and cannot be utilized for any other purposes than virtual memory. You can modify your virtual memory as you see fit by following these instructions:

Windows XP
To manually change the size of virtual memory, follow these steps:

  • Click Start, click Run, type sysdm.cpl in the Open box, and then press ENTER.
  • Click the Advanced tab, and then under Performance click Settings.
  • Click the Advanced tab, and then under Virtual memory click Change.
  • Under Drive [Volume Label], click the drive that contains the paging file that you want to change.
  • Under Paging file size for selected drive, click Custom size, type a new paging file size in megabytes (MB) in the Initial size (MB) and Maximum size (MB) box, and then click Set.
  • Click OK to close the dialog box and apply changes.
  • Note: After you change the size of the paging file, you may be prompted to restart Windows. If you are prompted to restart, the changes will not take effect until Windows is restarted.
  • For best results, it is highly recommended that you set/leave the paging file to 1.5 times your physical DRAM. This guide was created to explain Virtual Memory and assist you to verify that your page file is correctly configured after you perform a memory upgrade.

Windows Vista
Vista versions are set to automatically manage your Virtual Memory. To confirm or manually change these settings, follow these steps:

As an alternative to setting the AutomaticManagedPagefile property to False, follow these steps:

  • Click Start.
  • Click Control Panel, double-click System and Maintenance.
  • Click System.
  • Click Advanced system settings (note: you may be prompted for an administrator password, or confirmation, type the password, or provide confirmation).
  • In the System Properties dialog box, click the Advanced tab.
  • Under Performance, click Settings.
  • Click the Advanced tab, and then click Change under Virtual memory.
  • Click to clear the Automatically manage paging file size for all drives check box.
  • Click on Custom Size, fill in both the initial size and maximum size to 1.5 times the amount of physical DRAM you currently have installed.
  • Click Set, OK, and Apply.

Note: After you change the size of the paging file, you may be prompted to restart Windows. If you are prompted to restart, the changes will not take effect until Windows is restarted.

For best results, it is highly recommended that you set/leave the paging file to Windows Vista's recommended settings. This guide was created to explain Virtual Memory and assist you to verify that your page file is correctly configured after you perform a memory upgrade.