Int 10 Fn 4F00  - VESA SuperVGA BIOS - Get Supervga Information            [V]

   AX = 4F00h
   ES:DI -> 256-byte buffer for SuperVGA information (see below)

Return: AL = 4Fh function supported
   AH = status
       00h successful
       ES:DI buffer filled
       01h failed
Desc:  determine whether VESA BIOS extensions are present and the capabilities
     supported by the display adapter

See Also: AX=4F01h,AX=7F00h
Index: installation check;VESA

Format of SuperVGA information:
Offset Size    Description
 00h  4 BYTEs  signature ('VESA')
 04h   WORD    VESA version number
 06h   DWORD   pointer to OEM name
       "761295520" for ATI
 0Ah  4 BYTEs  capabilities
 0Eh   DWORD   pointer to list of supported VESA and OEM video modes
       (list of words terminated with FFFFh)
 12h   WORD    total amount of video memory in 64K blocks
 14h 236 BYTEs reserved

Notes: the list of supported video modes is stored in the reserved portion of
     the SuperVGA information record by some implementations, and it may
     thus be necessary to either copy the mode list or use a different
     buffer for all subsequent VESA calls
   the 1.1 VESA document specifies 242 reserved bytes at the end, so the
     buffer should be 262 bytes to ensure that it is not overrun