PAE (Physical Address Extension) enables your server to use more than 4 GB of RAM.

If you run Winver.exe and it reports more than 4 GB of memory, then the PAE specification is being used.

The /PAE switch in the C:\boot.ini file enables PAE, but some servers with hot plug memory enable PAE when the /PAE switch is NOT set in the C:\boot.ini file, unless the /NOPAE switch is set. The /NOPAE switch in the C:\boot.ini file disables PAE.

To verify that the /PAE switch is enabled on your server:

NOTE: The follow scriplet uses GetMEM.bat and VarLen.bat.                              set PAE=0x0                              :: NOTE: PAE is enabled when PAE=0x1                              call :getPAE>nul 2>&1                               if "%PAE%" NEQ "0x0" (                               @echo PAE is enabled on %ComputerName%. Memory is %MB% MB.                              ) ELSE (                               @echo PAE is NOT enabled on %ComputerName%. Memory is %MB% MB.                              )                              . . .                              . . .                              :getPAE                              call GetMem MB                              set key="HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management"                              for /f "Tokens=2*" %%a in ('reg query %key% /V PhysicalAddressExtension^|find "REG_DWORD"') do (                               set PAE=%%b                              )                              goto :EOF