WinForms - konwersja z int na hex do label

private: System::Void get_serial_number( System::Object ^ sender, System::Windows::Forms::MouseEventArgs ^ e )
{
    DWORD disk_serial;
    GetVolumeInformationA( "C:\\", NULL, NULL, & disk_serial, NULL, NULL, NULL, NULL );
    unsigned int x = disk_serial;
    std::stringstream stream;
    stream << std::hex << x;
    std::string result = stream.str();
    this->label1->Text = Convert::ToString( stream.str() );
   
}
};