IS A COMPUTER A 32 OR 64 BITS?

How to determine whether the computer is a 32 or 64 Bits

Windows XP

If you have Windows XP, there are two methods to determine whether you are running a 32-bit or a 64-bit version. If one does not work, try the other.

Method 1: View System Properties in Control Panel

1. Click Start, and then click Run.
2. Type sysdm.cpl, and then click OK.
3. Click the General tab. The operating system is displayed as follows:

• For a 64-bit version operating system: Windows XP Professional x64 Edition Version < Year> appears under System.
• For a 32-bit version operating system: Windows XP Professional Version <Year> appears under System.

Note <Year> is a placeholder for a year.

Method 2: View System Information window

1. Click Start, and then click Run.
2. Type winmsd.exe, and then click OK.
3. When System Summary is selected in the navigation pane, locate Processor under Item in the details pane. Note the value.

• If the value that corresponds to Processor starts with x86, the computer is running a 32-bit version of Windows.
• If the value that corresponds to Processor starts with ia64 or AMD64, the computer is running a 64-bit version of Windows.

If you cannot determine the operating system bit count with these methods, go to the "Next Steps" section.

How to run multi- boot

This article explains how to set up Windows XP as a multiple-boot system with the following operating systems:

• Microsoft Windows 2000, Microsoft Windows NT 4.0, and Microsoft Windows NT 3.51
• Microsoft Windows 95 Operating System Release 2 (OSR2), Microsoft Windows 98, and Microsoft Windows Millennium Edition (Me)
• MS-DOS or Microsoft Windows 3.x

You can install more than one operating system on your computer and choose which operating system you want to use every time you start your computer. This is often called a dual-boot or multiple-boot configuration (see the glossary at the end of this article for definitions of unfamiliar terminology).

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Disk Volumes and Disk Format

Note that Encrypting File System (EFS) is not available in the Windows XP Home Edition.

Reformatting and Repairing the Hard Disk

You may need to reformat and repartition your hard disk if:

• You have only one volume.

  You have to install each operating system on a separate volume of your computer so that each installation can retain its own files and configuration information.

• The boot partition is not formatted with the correct file system:

• If you want to create a multiple-boot system by using MS-DOS, Windows 95, Windows 98 or Windows Me, you have to format the system partition by using FAT16 or FAT32 because the operating system cannot start if the system partition is NTFS.
• If you want to create a multiple-boot system by using Windows 95, Windows 98 or Windows Me along with Microsoft Windows XP, you have to format the boot partition by using FAT16 because Windows 95, Windows 98 and Windows Me do not support the NTFS file system.
• If you want to install Windows 95, Windows 98, or Windows Me with Windows NT 4.0, Windows 2000, or Windows XP, you can format the boot partition by using FAT16 because Windows NT 4.0 does not support the FAT32 file system.
• If you want to create a multiple-boot system using Windows 98 or Windows Me with Windows 2000, or Windows XP, you can format the boot partition by using FAT32.

  Note If you format a Windows NT 4.0, Windows 2000, or Windows XP volume with any file system other than NTFS, you will lose all NTFS-specific features. This includes some Windows XP features such as file system security, Encrypting File System (EFS) settings, disk quotas, and Remote Storage. Likewise, Windows 95, Windows 98, and Windows Me do not recognize an NTFS partition and identify it as unknown. Therefore, if you format a Windows 98 or Windows Me partition as FAT, and a Windows XP partition as NTFS, any files on the NTFS partition will not be available or visible if you try to access them while running Windows 98 or Windows Me.

Supported File Systems

The following table lists the supported file systems for Microsoft operating systems:

 Operating system Supported file systems