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LabVIEW is large address aware, and can take advantage of up to 3 or 4 GB of virtual memory. On 32-bit Windows, LabVIEW can access up to 2 GB of virtual memory by default. To take advantage of additional virtual memory, you must modify the Windows boot configuration settings. Windows stores boot configuration settings differently on Windows Vista and Windows XP/2000. This topic includes procedures for modifying boot configuration settings based on the Windows version you use.

Note  On 64-bit Windows, LabVIEW can access up to 4 GB of virtual memory by default. You do not have to take any action to enable LabVIEW to access up to 4 GB of virtual memory on 64-bit Windows.

Enabling LabVIEW to Use up to 3 GB of Virtual Memory on Windows Vista

(Windows Vista) Complete the following steps to modify the Windows boot configuration settings and enable LabVIEW to access up to 3 GB of virtual memory.

1. Open the command line window as an administrator.
   1. Navigate to the command line window in the Windows Start menu.
   2. Right-click the program name and select Run as administrator from the shortcut menu.
   3. When prompted, enter the Windows administrator user name and password. If you are already logged in as the Windows administrator, click the Continue button in the dialog that appears. Only the administrator can modify the boot configuration settings.
2. Enter the command bcdedit /enum and press the <Enter> key to show the list of entries in the Boot Configuration Data (BCD) store. These settings control how the OS launches.
3. Enter the command bcdedit /set increaseuserva 3072 and press the <Enter> key. This command increases the amount of virtual memory that the OS allots to the user to 3072 MB, or 3 GB.
4. Restart the system for the changes to the BCD store to take effect.

Enabling LabVIEW to Use up to 4 GB of Virtual Memory on Windows Vista

(Windows Vista) If you have more than 4 GB of physical RAM, you can enable LabVIEW and other applications that are large address aware to access up to 4 GB of virtual memory. Complete the following steps to modify the Windows boot configuration settings and enable LabVIEW to access up to 4 GB of virtual memory.

1. Open the command line window as an administrator.
   1. Navigate to the command line window in the Windows Start menu.
   2. Right-click the program name and select Run as administrator from the shortcut menu.
   3. When prompted, enter the Windows administrator user name and password. If you are already logged in as the Windows administrator, click the Continue button in the dialog that appears. Only the administrator can modify the boot configuration settings.
2. Enter the command bcdedit /enum and press the <Enter> key to show the list of entries in the Boot Configuration Data (BCD) store. These settings control how the OS launches.
3. Enter the command bcdedit /set pae ForceEnable and press the <Enter> key. This command enables Physical Address Extension (PAE) and enables LabVIEW and other applications that are large address aware to access up to 4 GB of virtual memory.
4. Restart the system for the changes to the BCD store to take effect.

Enabling LabVIEW to Use up to 3 GB of Virtual Memory on Windows XP/2000

(Windows XP/2000) Complete the following steps to modify the Windows boot configuration settings and enable LabVIEW to use up to 3 GB of virtual memory.

1. Locate the Windows boot.ini file. Windows stores this file on the C drive. However, this file does not appear if you configure Windows Explorer to not display system files. Complete the following steps if you do not see the boot.ini file in the C:/ directory.
   1. In Windows Explorer, enter C:/boot.ini in the Address bar.
   2. The boot.ini file opens in the default text editor.
2. Save a back-up copy of the boot.ini file to a location that you can access outside of the operating system.
3. In the original boot.ini file, find the line that specifies the version of Windows to boot. The following example shows how this line might appear on a system running Windows XP:
   
   [operating systems]
   multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin/fastdetect
4. Add the tag /3GB to the end of the line. This tag tells the OS to use only 1 GB of virtual memory for the kernel, or central component, of the OS, leaving the other 3 GB of virtual memory for the application.
5. Save and close the boot.ini file.
6. Restart the system for the changes to the boot.ini file to take effect.

Enabling LabVIEW to Use up to 4 GB of Virtual Memory on Windows XP/2000

(Windows XP/2000) Complete the following steps to modify the Windows boot configuration settings and enable LabVIEW to use up to 4 GB of virtual memory.

1. Locate the system boot.ini file. Windows stores this file on the C drive. However, this file does not appear if you configure Windows Explorer not to display system files. Complete the following steps if you do not see the boot.ini file in the C:/ directory.
   1. In Windows Explorer, enter C:/boot.ini in the Address bar.
   2. The boot.ini file opens in the default text editor.
2. Save a back-up copy of the boot.ini file to a location that you can access outside of the operating system.
3. In the original boot.ini file, find the line that specifies the version of Windows to boot. The following example shows how this line might appear on a system running Windows XP:
   
   [operating systems]
   multi(0)disk(0)rdisk(0)partition(2)\WINDOWS="Microsoft Windows XP Professional" /noexecute=optin/fastdetect
4. Add the tag /PAE to the end of the line. This tag enables Physical Address Extension (PAE), and enables LabVIEW and other applications that are large address aware to access up to 4 GB of virtual memory.
5. Save and close the boot.ini file.
6. Restart the system for the changes to the boot.ini file to take effect.

Refer to the Microsoft Web site for more information about the Boot Configuration Data store, boot.ini file, and Physical Address Extension.