How do I tell if my computer can run a 64-bit version of Windows?

To run a 64-bit version of Windows, your computer must have a 64-bit-capable processor. To determine if your processor is 64-bit-capable, Open Performance Information and Tools by clicking the Start button and then clicking Control Panel. In the search box, type Performance Information and Tools, and then, in the list of results, click Performance Information and Tools.  Click View and print detailed performance and system information.  In the System section, you can see what type of operating system you're currently running under System type and whether or not you can run a 64-bit version of Windows under 64-bit capability. (If your computer is already running a 64-bit version of Windows, you won't see the 64-bit capable listing.)