response 56 of 257:

Feb 12 03:24 UTC 1999

The superblock is just the first block of a partition.  If there is 
nothing in the MBR, such as if you've just gotten a new hard drive or 
just installed windows, then the BIOS runs the program in the first 
block (read superblock) the the partition marked active.  It has the 
same kind of space restrictions as the MBR, almost.  If the BIOS is 
running it, it needs to be withing BIOS addressable space, which is 1024 
if you have a brain-dead BIOS. (If so, upgradeing your BIOS will almost 
certainly cure it.)  

Re: FreeBSD screw-up:  I run FreeBSD as the only OS on my computer at 
work, and I've installed any number of times, with no problem.  From 
what you've said, it sounds like no partition was marked as active, 
and/or you didn't install the FreeBSD Bootloader.  That's optional.