0:463h                   CRT Controller Base Address

Length: 2 bytes

Holds the CRT Controller Base Address. You can easily determine the
current active display adapter by looking at this value. This base
address is the video controller index register. This register is used
to select which video controller register is to be accessed.

                 The value at this location is either:

3B4h for Monochrome, or
3D4h for Color Graphics Adapter

See also: 0:465h
See also: 0:466h

0:463h CRT Controller Base Address