Int 16 Fn F0  - Compaq 386 And Newer - Set Cpu Speed                       [b]

   AH = F0h
   AL = speed code (see #0538)
   if AL=09h,
       CX = speed value, 1 (slowest) to 50 (full), 3 ~= 8088

Note:  also supported by some versions of AMI BIOS dated June 1992 or later;
     speed codes 0 or 1 are used for Low Speed, 2 for High Speed

See Also: AH=F1h,AH=F3h

(Table 0538)
Values for speed code:
 00h   equivalent to 6 MHz 80286 (COMMON)
 01h   equivalent to 8 MHz 80286 (FAST)
 02h   full 16 MHz (HIGH)
 03h   toggles between 8 MHz-equivalent and speed set by system board switch
     (AUTO or HIGH)
 08h   full 16 MHz except 8 MHz-equivalent during floppy disk access
 09h   specify speed directly