How can I find out whether my Windows is 32 bit or 64 bit?

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 Collapse this imageExpand this image Start button , type system in the Start Search box, and then click system in the Programs list.
2. The operating system is displayed 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 Collapse this imageExpand this image Start button , 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.

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.

Method 1: System Manager

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 appears under System. Note 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.

As for hardware question, what hardware are you running?

Quick way to determine if your copy of Windows is 64-bit:

• Press Windows-Break key combination
• Look for x64 in the System Properties

Vista:

• Press Windows-Break key combination
• Look for System Type

How to tell if your processor supports 64-bit extensions from looking at the part:

• AMD: Any AMD K8 or newer based part is 64-bit unless sold as 32-bit only. This includes Athlon 64 or Opteron, and all the Athlon X2's and higher are 64-bit and some Semperons
• Intel: I actually don't know how to determine it is 64-bit other than looking for EM64T designation for the part. Maybe somebody else can have a better answer here.

If you are running the part, just run CPU-Z on it.

Motherboard:

• It just has to support a processor that is 64-bit.

msinfo32

Start -> Run -> msinfo32

Both OS type and system type have been highlighted: