Int 62 Fn 008B  u - Fgdriver V4.02 - "fg_pcxmode" - Get Optimal Video Mod  [V]

   AX = 008Bh
   ES:BX -> PCX header (see AX=008Ah)

Return: AX = optimal video mode for PCX file
       FFFEh not a valid PCX header
       FFFFh unable to determine compatible video mode

Note:  the FGDRIVER functions are rearranged with each major release, but
     their parameters do not change (see #3145 at AX=0000h)

See Also: AX=008Ah,AX=00B9h