wpf textbox content freezes ui on load

Question

I started coding my first WPF app and I'm having trouble with a textbox that displays some system info (cpu, memory, disk usage, mac address, etc.). My apps has navigation between two pages and the said textbox is on one of the pages. The textbox's content is retrieved via WMI queries. The issue I have noticed is that while navigating to tha page with the textbox it freezes the UI for about two seconds before going to and display the page. I'm a newbie and my best guess is that eighter the WMI queries(could be badly coded too) are doing that or I'm loading the content in the textbox wrongfully. An example of how my queries are constructed

public string getCPU()
    {
        ManagementObjectSearcher searcher = new
        ManagementObjectSearcher("root\\CIMV2", "SELECT * FROM Win32_Processor");
        StringBuilder sb = new StringBuilder();
        foreach (ManagementObject wmi in searcher.Get())
        {
            try
            {
                sb.Append("Processor: " + wmi.GetPropertyValue("Name").ToString() + Environment.NewLine);
            }
            catch
            {
                return sb.ToString();
            }
        }
        return sb.ToString();
    }
    public string getRAMsize()
    {
        ManagementClass mc = new ManagementClass("Win32_ComputerSystem");
        ManagementObjectCollection moc = mc.GetInstances();
        foreach (ManagementObject item in moc)
        {
            return Convert.ToString(Math.Round(Convert.ToDouble(item.Properties["TotalPhysicalMemory"].Value) / (1024 * 1024 * 1024), 0)) + " GB";
        }

        return "RAMsize";
    }

And this is what I use to retrieve the data in the textbox:

private void TextBox1_Loaded(object sender, RoutedEventArgs e)
    {
        TextBox1.Text = getCPU();
        TextBox1.Text += "Memory:  " + getRAMsize() + Environment.NewLine;
        TextBox1.Text += "Free Space:  " + GetTotalFreeSpace(sysdrive) + " GB" + Environment.NewLine;
        if (Is64BitSystem)
        {
            TextBox1.Text += getOS() + " 64bit" + Environment.NewLine;
        }
        else
        {
            TextBox1.Text += getOS() + " 32 Bit" + Environment.NewLine;
        }
        TextBox1.Text += "MAC Address : " + System.Text.RegularExpressions.Regex.Replace(GetMacAddress().ToString(), ".{2}", "$0 ") + Environment.NewLine;
        TextBox1.Text += av();
    }

My question is what am I doing wrong and how can I get around with it. In my mind , if the queries are constructed correctly, it would be because they are done again and again everytime the textbox is loaded (on navigation or at startup) and maybe If I could get it to load only once and remember those values(since most of the data should stay the same). But as I said I'm a noob and any help will be greatly appreciated. Thanks in advance

Answer 1

After checking each and every query I found out that the getCPU one is causing a delay in the load. I replaced it with a Registry.GetValue, wich is very fast. Thanks to Sebastian L, because altough his code didn't work for me it put me on the right path and I was able to adapt own code with a backgroundworker to avoid UI freeze of any kind my working code:

private void TextBox1_Loaded(object sender, RoutedEventArgs e)
    {

        BackgroundWorker bw = new BackgroundWorker();
        bw.WorkerReportsProgress = true;
        bw.DoWork += new DoWorkEventHandler(delegate (object o, DoWorkEventArgs args)
        {

        });
        bw.RunWorkerCompleted += new RunWorkerCompletedEventHandler(delegate (object o, RunWorkerCompletedEventArgs args)
        {
            TextBox1.Text = (string)Registry.GetValue(@"HKEY_LOCAL_MACHINE\HARDWARE\DESCRIPTION\System\CentralProcessor\0", "ProcessorNameString", null) + Environment.NewLine;
            TextBox1.Text += "Memory:  " + getRAMsize() + Environment.NewLine;
            TextBox1.Text += "Free Space:  " + GetTotalFreeSpace(sysdrive) + " GB" + Environment.NewLine;
            if (Is64BitSystem)
            {
                TextBox1.Text += getOS() + " 64bit" + Environment.NewLine;
            }
            else
            {
                TextBox1.Text += getOS() + " 32 Bit" + Environment.NewLine;
            }
            TextBox1.Text += "MAC Address : " + System.Text.RegularExpressions.Regex.Replace(GetMacAddress().ToString(), ".{2}", "$0 ") + Environment.NewLine;
            TextBox1.Text += av();
        });
        bw.RunWorkerAsync();
    }