I searched a few times to avoid asking something that has been discussed already, so if I am doing so anyway, or if the answer is obvious and I am just dense...

My system: a four year old 686. Pentium III 500mHz, 256MB RAM, a master 120GB HD that is all one DOS partition (foolish error, yes, but I didn't know any better at the time) and a slave HD that is 20GB Maxtor.

The second disk is the problem. Out of the box, the 20GB was the machine's original and only HD. After I installed the 120GB for movies and mp3s, the 20GB became the Linux playground. Now, running Knoppix from the CD, it could see the entire 20GB DOS partition that was there. (Knoppix cannot mount the 120 as it is, of course ) But when I decided to go for the poor man's install, I wanted the "CD" to have its own partion, and discovered that both cfdisk and qtparted see only an 8 GB disk there. First, both told me the existing partition exceeded the disk space and could not proceed. So from DOS I used fdisk. As a blank, unformatted disk, cfdisk and qtparted still only saw 8GB. It would allow me to make DOS and ext2 partitions with that 8GB, but it did not see the remaining space. I tried every thing I could think of--included loading up the diskwith several small partitions with fdisk, hoping I could reformat them with qtparted--but no matter what, Knoppix sees 8 GB and DOS sees 20, unless I make a DOS partition of the whole drive and run Knoppix from the CD, but then it can only read and write to the disk, not reformat it.

The current setup is I have two partitions, hdb1 with about 6GB for files, and hdb2 with about 2GB for the poor man's install. From DOS/Windows, fdisk sees a drive with 8GB formatted and 12GB free, while Linux sees only 8GB.

I can live that, but I would really like to understand what the problem is. I probably don't need even the 8GB, truth be told, but I would really like to understand what is going on here. I would like to do a proper install to this disk oneday, but I would want the entire disk if I did so.