Does anyone know of any good documentation on manually (using BIOS
geometry or sector offsets and sizes) dividing a hard drive into
partitions using fdisk?

I know that most fdisks allow you to easily enter data using size entries
in megabytes or kilobytes.

But I need/want to learn how to create partitions by just using starting
cylinders, heads and sectors and ending cylinder, heads and sectors or by
using start sectors and size in sectors.

(Usually it is a lot of trial and error for me. I want to learn how to do
it correctly.)

Or if you can explain how to do it, I'd appreciate it. For example, I have
a hard drive that a kernel says is 6149 MB, 13328 cylinders, 15 head
(tracks per cylinder), 63 sectors per track and 12594960 sectors. My fdisk
geometry says it is 783 cylinders, 255 head (tracks per cylinder), 63
sectors per track and 12578895 sectors. (I am also unclear of why these
differences.) I want to break this up into three partitions:
 150 MB
 2000 MB
 2000 MB
How can I easily figure out the starting and ending cyl, hd and sec or the
starting sector and size (in sectors) of each?

Thanks,

  Jeremy C. Reed
  http://www.reedmedia.net/
  http://bsd.reedmedia.net/