The default value for registers and segments when loading the x86 machine

Question

I found that usually programmers fix registers (and sometimes segments) on their first lines of bootloaders, and they usually advise for this. For instance:

inc cx
dec bx
inc bp
dec di
xor ax, ax

Interestingly, I know: the BIOS clears all registers during the boot procedure.

Is it good to initialize registers and segments in the bootloader? If so, what are the default values ​​for registers, segments, and pointers (perhaps dependent on the chipset)?

Answer 1

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