The ColorTableEntries property indicates the number of color indexes in a color table for a video display. This property ...

The ColorTableEntries property indicates the number of color indexes in a color table for a video display. This property is used if the device has a color depth of no more than 8 bits per pixel. For devices with greater color depths, -1 is returned.
Example: 256  
This property has been deprecated in favor of a corresponding property(s) contained in the Win32_VideoController, Win32_DesktopMonitor and//or CIM_VideoControllerResolution