Computers running Windows XP

·         Click Start, right-click My Computer, and then click Properties.

·         If "x64 Edition" is listed under System, you’re running the 64-bit version ofWindows XP.

·         If you don’t see "x64 Edition" listed under System, you’re running the 32-bit version of Windows XP.

The edition of Windows XP you're running is displayed under System near the top of the window.



Computers running Windows Vista or Windows 7

·         Click the Start button in lower-left corner of your screen , right-click Computer, and then click Properties.

·         If "64-bit Operating System" is listed next to System type, you’re running the 64-bit version of Windows Vista or Windows 7.

·         If "32-bit Operating System" is listed next to System type, you’re running the 32-bit version of Windows Vista or Windows 7.

The edition of Windows Vista or Windows 7 you're running is displayed underWindows edition near the top of the window.