David Wilkinson

John Barnes wrote:

> The mbr looks up in its tables the active partition and reads the boot
> sector for the bootloader, which has to be on that (system drive) for
> Windows. If it is XP it points to ntldr, if Vista to the boot file. As far
> as ntldr is concerned, that performs several functions one of which is to
> read the boot.ini and either goes driectly to the boot drive in the boot.ini
> or presents the menu to select from multiple boot drives. On the boot
> partition it loads the ntoskrnl.exe and hal.dll starting XP. Don't know
> the process for Vista.
>

The MBR does not load a file on the active (boot) partition; rather it
transfers control to some address in the boot sector of the active
partition. It seems to me that this address must be the same for a
machine that has only XP on it, and one that has only Vista, and one
that has both. That is why the MBR can be (essentially) the same for
different OS's.

David Wilkinson