Int 15 Fn BFDE  - Desqview/x 1.02+ - Dvdos4gx.dvr - ???                    [E]

   AX = BFDEh
   BX = 0005h
   CX = new value for ???

Return: BX = 0000h (success)
   AX = old value of ???
   DS:SI -> ??? (if AX nonzero on return)
   ES:DI -> ??? (if AX zero on return)

Note:  called by DOS4GW.EXE

See Also: AX=BFDEh/BX=0000h