FFFFh:0000h           FAR JMP to Beginning of Power-On Self Test (POST)

    Length: 5 bytes

    Located at this address is a far jump to the beginning of the
    Power-On Self Test (POST).

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    See POST for more details on what it does. The reason this address
    is used for this purpose is that when the 8086 family of
    microprocessors receive power, the CS register is set to FFFFh and
    the IP register to 0.

    If you wish to reboot (either warm or cold) a system, perform a
    far jump to this address. This will force the POST to take
    control, which will reboot the system. The POST looks at the word
    at address 0040h:0072h to determine whether a warm boot or a cold
    boot should be performed. If the value at 0040h:0072h is 1234h,
    then a warm boot is performed; otherwise the boot is cold.