The DisplayFrequency property indicates the display's vertical refresh rate. The refresh rate for a monitor is the number ...

The DisplayFrequency property indicates the display's vertical refresh rate. The refresh rate for a monitor is the number of times the screen is redrawn per second (frequency).  
This property has been deprecated in favor of a corresponding property(s) contained in the Win32_VideoController, Win32_DesktopMonitor and//or CIM_VideoControllerResolution