How can I programmatically determine my processor type?

Question

How can I determine programmatically whether my machine is an x86, x64 or an IA64?

Answer 1

In C#:

using System;
using Microsoft.Win32;

  class Class1
  {
    static void Main(string[] args)
    {
      RegistryKey RegKey = Registry.LocalMachine;
      RegKey = RegKey.OpenSubKey("HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0");
      Object cpuSpeed = RegKey.GetValue("~MHz");
      Object cpuType  = RegKey.GetValue("VendorIdentifier");
      Console.WriteLine("You have a {0} running at {1} MHz.",cpuType,cpuSpeed);
    }
  }