It's not available
Win32_VideoConfigurationThe Win32_VideoConfiguration WMI class represents a configuration of a video subsystem.
Warning This class has been eliminated from Windows XP and later; attempts to use it will generate a fatal error. In place of this class, you should use the properties contained in the Win32_VideoController, Win32_DesktopMonitor, and CIM_VideoControllerResolution classes.
BTW:
The "NumberOfCores" property referred to above is not available before Vista.
