How to detect CPU speed on Windows 64bit?

Question

I've found the following code from here "http://www.boyet.com/Articles/CodeFromInternet.html".
It returns the speed of the CPU in GHz but works only on 32bit Windows.

using System;
using System.Management;

namespace CpuSpeed
{
    class Program
    {
        static double? GetCpuSpeedInGHz()
        {
            double? GHz = null;
            using (ManagementClass mc = new ManagementClass("Win32_Processor"))
            {
                foreach (ManagementObject mo in mc.GetInstances())
                {
                    GHz = 0.001 * (UInt32) mo.Properties["CurrentClockSpeed"].Value;
                    break;
                }
            }
            return GHz;
        }

        static void Main(string[] args)
        {
            Console.WriteLine("The current CPU speed is {0}", (GetCpuSpeedInGHz() ?? -1.0).ToString());
            Console.ReadLine();
        }
    }
}

I've searched for 64bit management classes, but without success.
Is there any other method to get the CPU speed under 64bit Windows?

Uhm.. what makes you think that this only works on 32bit Windows? — Christian.K, Oct 07 '11 at 07:32

Binoj Antony · Answer 1 · 2009-03-16T15:04:00.617

6

Code below should do the trick

  RegistryKey registrykeyHKLM = Registry.LocalMachine;
  string keyPath = @"HARDWARE\DESCRIPTION\System\CentralProcessor\0";
  RegistryKey registrykeyCPU = registrykeyHKLM.OpenSubKey(keyPath, false);
  string MHz = registrykeyCPU.GetValue("~MHz").ToString();
  string ProcessorNameString = (string)registrykeyCPU.GetValue("ProcessorNameString");
  registrykeyCPU.Close();
  registrykeyHKLM.Close();
  Console.WriteLine("{0} MHz for {1}", MHz, ProcessorNameString);

edited Mar 16 '09 at 15:04

answered Dec 11 '08 at 14:42

Binoj Antony

15,886
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I've rewritten the code as contained some bugs and only returned the MHz for CPU/code 0. See my marked reply. Thanks a lot for your code as well. – Marc Mar 16 '09 at 15:00

score 0 · Answer 2 · answered Aug 17 '11 at 15:50

0

A simpler version of the answer provided by Binoj would be as follows. This will return the maximum clock speed of your CPU. Please note that if you want the total available cycles on the machine you should multiply this value by Environment.ProcessorCount.

private float GetCpuClockSpeed()
{
    return (int) Registry.GetValue(@"HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0", "~MHz", 0);
}

answered Aug 17 '11 at 15:50

Jon Norton

2,969
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Take note that although most processors on the market today use same clock for all cores but there might be some that don't. you have to sum all speeds for all cores. – Daniel Aug 17 '11 at 15:54

Marc · Accepted Answer · 2009-03-17T10:02:38.383

I've used the following code based on the answer by Binoj Antony which returns the speed for each CPU/core, not only the first one:

Microsoft.Win32.RegistryKey registrykeyHKLM = Microsoft.Win32.Registry.LocalMachine;
string cpuPath = @"HARDWARE\DESCRIPTION\System\CentralProcessor";
Microsoft.Win32.RegistryKey registrykeyCPUs = registrykeyHKLM.OpenSubKey(cpuPath, false);
StringBuilder sbCPUDetails = new StringBuilder();
int iCPUCount;
for (iCPUCount = 0; iCPUCount < registrykeyCPUs.SubKeyCount; iCPUCount++)
{
    Microsoft.Win32.RegistryKey registrykeyCPUDetail = registrykeyHKLM.OpenSubKey(cpuPath + "\\" + iCPUCount, false);
    string sMHz = registrykeyCPUDetail.GetValue("~MHz").ToString();
    string sProcessorNameString = registrykeyCPUDetail.GetValue("ProcessorNameString").ToString();
    sbCPUDetails.Append(Environment.NewLine + "\t" + string.Format("CPU{0}: {1} MHz for {2}", new object[] { iCPUCount, sMHz, sProcessorNameString }));
    registrykeyCPUDetail.Close();
}
registrykeyCPUs.Close();
registrykeyHKLM.Close();
sCPUSpeed = iCPUCount++ + " core(s) found:" + sbCPUDetails.ToString();

Fell free to customize it for your needs.

does this return the current speed or the maximum speed? – Nathan Fellman Mar 17 '09 at 10:53 — Nathan Fellman, Mar 17 '09 at 10:53

How to detect CPU speed on Windows 64bit?

3 Answers3