It's perfectly fine for both OSes to share the same paging file> Clearing the paging file: Windows XP: Bring up regedit.exe Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager Create a new DWORD value, or modify the existing value, called "ClearPageFileAtShutdown" and set it to "Value Data" 1 (enables clearing pagefile), 0 (disables it). The above change won't take effect until the next re-boot. Vista: Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management Change "ClearPageFileAtShutdown" to 1.