How to Check if Windows XP is 32 or 64 Bit

Microsoft Windows XP was available in Home and Professional versions, with the Home edition available as 32-bit only. The Professional edition was available as either 32-bit or 64-bit. In order to run the Windows XP Professional 64-bit version, the computer's processor must also be 64-bit, meaning it can process twice as much data in a single operation as a 32-bit processor. This allows data to be processed faster, and more RAM to be addressed, removing the four gigabyte memory limit faced by 32-bit operating systems. To check if your copy of Windows XP is 32-bit or 64-bit you can use the Windows Control Panel.

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Windows XP Professional was the only edition to be released as 32-bit or 64-bit.

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Click on the Windows "Start" button and select "Control Panel" from the Windows "Start" menu.

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Double-click on the "System" icon to open the system properties dialog box.

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Click on the "General" tab and look under the "System" section. If the operating system is listed as "Windows XP Professional x64 Edition" or "Windows XP Professional 64-bit Edition" the operating system is 64-bit. If the operating system is listed as "Windows XP Professional Version," the operating system is 32-bit.