>> The method I've used in my OS is to make a far jump to make sure
>> I'm in 07c0:0000 and not in 0000:7c00. I discovered this because
> Hmm.. I don't quite follow.. How do you use a far jump to make sure?
> But apart from that, are those the only two places the boot sector could be
> loaded?
Those are the same location, adressed in two different ways. There is a 
significant difference, though. Example code: (NASM)
[BITS 16]
[SECTION .text]
[ORG 0x0000]
       JMP entry
... sett inn OEM boot sector data ... entry  JMP FAR 0x07c0:start
start  .. code ..
--- BBBS/NT v3.33 How
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