The RefreshRate property indicates the refresh rate of the video adapter. A value of 0 or 1 indicates a default rate is being ...

The RefreshRate property indicates the refresh rate of the video adapter. A value of 0 or 1 indicates a default rate is being used. A value of -1 indicates that an optimal rate is being used.
Example: 72  
This property has been deprecated in favor of a corresponding property(s) contained in the Win32_VideoController, Win32_DesktopMonitor and//or CIM_VideoControllerResolution