generate unique computer identifier sample

 public static class cCHID
    {
        public static string GetCHID()
        {
            string CHID = "";

            ManagementObjectSearcher searcher;

            //processor
            searcher = new ManagementObjectSearcher("root\\CIMV2",
                   "SELECT * FROM Win32_Processor");
            foreach (ManagementObject queryObj in searcher.Get())
                CHID = CHID + queryObj["ProcessorId"].ToString() + "_";

            //mainboard id
            searcher = new ManagementObjectSearcher("root\\CIMV2",
                   "SELECT * FROM CIM_Card");
            foreach (ManagementObject queryObj in searcher.Get())
                CHID = CHID + queryObj["SerialNumber"].ToString() + "_";

            //OS serial number
            searcher = new ManagementObjectSearcher("root\\CIMV2",
                   "SELECT * FROM CIM_OperatingSystem");
            foreach (ManagementObject queryObj in searcher.Get())
                CHID = CHID + queryObj["SerialNumber"].ToString();

            return CHID;
        }

    }