Int 13 Fn FFFF  - Unique Ux Turbo Utility - Set Turbo Mode                 [U]

   AX = FFFFh
   BH = AAh
   BL = subfunction
       00h installation check

       Return: AX = 1234h if installed
       01h turn on Turbo mode
       02h turn off Turbo mode
       03h set Turbo mode according to hardware switch
       04h set disk access to Turbo mode
       05h set disk access to Normal mode

See Also: INT 15/AH=DFh
Index: installation check;UNIQUE UX Turbo Utility