Int 15 Fn CCCC  U - Toshiba Laptops - Vchad.exe - Installation Check       [V]

   AX = CCCCh

Return: AX = ABCDh if installed

Note:  supported by Toshiba VGA change display utility VCHAD.EXE ver 2.90+
     older versions have the string "VCHAD" 2 bytes after the address of
     the INT 15 handler which is hooked by all versions for the SysReq key

See Also: AH=85h