Problems about Grub and FreeBSD

[殷鸣]

Hi, all
I got some problems while installed FreeBSD onto a big disk. 

I installed 3 OS on my box, WIN98, Redhat9, and FreeBSD5r. BSD is resident
in the third partition, from 768cyl to 1800cyl, but the bios of my box
is rather old, which doesn't support big disks greater than 1024cyl. I
should have set a boot disk label in the 1024cyl, but I forgot to do
that. So, for either Grub (0.93) and bootmgr of BSD, they cannot load
the kernel directly.

Partition:
[0-767cyl WIN98] [768-1800cyl BSD] [...]

Disk label inside BSD partition:
[ / size:as much as this partition ] [ swap size:256M]

First question, how to load BSD's kernel outside of 1024cyl? My bios has
no version supporting big disks.

Second: I installed Grub in MBR, to boot these 3 OS. Since it wasn't
able to load the BSD's kernel outside of 1024cyl, I tried chainloader as
same as WIN98:
#grub.conf
rootnoverify (hd0,1) # the BSD partition
makeactive
chainloader +1

It worked, Grub loaded the boot sector of BSD partition and then, the
later one loaded the kernel correctly. But the loading was rather slow.
I mean, loading of kernel is rathr slow (takes about 20 seconds) , but
after kernel having been loaded, the system runs as fast as usual. 
Why?