How to determine bit version of the Windows operating system

Introduction

This article describes how to determine whether a computer is running a 32-bit Windows operating system or a 64-bit Windows operating system. Generally, a computer's bit count indicates how much data it can process, the speed with which it can process the data, and also the memory capacity. The bit count of the operating system installed on the computer should match the bit count of the computer in order to optimize the computer's performance.

This article is intended for a beginning to intermediate computer user. You may find it easier to follow the steps if you print this article first.


Determine the operating system bit count

Locate the operating system that is running on your computer in this section, and then follow the steps to determine the bit count of your operating system.

Determining bit version in Windows Vista

If you have Windows Vista, 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 window in Control Panel

1. Click Start, type system in the Start Search box, and then click system in the Programs list.
   
   
2. The operating system appears as follows:
   
   • For a 64-bit version operating system: 64-bit Operating System appears for the System type under System.
   • For a 32-bit version operating system: 32-bit Operating System appears for the System type under System.

Method 2: View System Information window

1. Click Start, type system in the Start Search box, and then click System Information in the Programs list.
   
   
2. When System Summary is selected in the navigation pane, the operating system is displayed as follows:
   
   • For a 64-bit version operating system: x64-based PC appears for the System type under Item.
   • For a 32-bit version operating system: x86-based PC appears for the System type under Item.

Determining bit version in 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 appears as follows:
   
   • For a 64-bit version operating system: Microsoft Windows XP Professional x64 Edition Version <Year> appears under System.
   • For a 32-bit version operating system: Microsoft 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 the Windows operating system.
   • If the value that corresponds to Processor starts with ia64 or AMD64, the computer is running a 64-bit version of the Windows operating system.

Determining bit version in Windows Server 2003

If you have Windows Server 2003, 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: Microsoft Windows Server 2003 Enterprise x64 Edition appears under System.
   • For a 32-bit version operating system: Microsoft Windows Server 2003 Enterprise Edition appears under System.

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 the Windows operating system.
   • If the value that corresponds to Processor starts with EM64T or ia64, the computer is running a 64-bit version of the Windows operating system.

Quote:

---

Note: Intel Itanium-based computers can only run 64-bit versions of Windows. Intel Itanium-based computers cannot run a 32-bit Windows operating system. Currently, 64-bit versions of Windows only run on Itanium-based computers and AMD64-based computers.

---