12479 unallocated sectors -- Dell MediaDirect?

[Zolcos]

After successfully dualbooting my tower I thought I'd do the same to my new laptop. It is a Dell Inspiron E1505 that comes with a minimal boot media center thing called "mediadirect" that I didn't care to keep, especially since support for this came in the form of a fairly miserable partition layout. I decided to junk the whole setup and start clean.

I deleted all the partitions and installed Vista x64 over the entire disk. I then resized the NTFS partition to about 60GB leaving the rest unallocated.
I booted my Gentoo LiveCD and created the following partition layout:

Disk /dev/sda: 120.0 GB
255 heads, 63 sectors/track, 14593 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device		Boot	Start	End	Blocks		Id	System
/dev/sda1	*	1	10769	86498304	7	HPFS/NTFS
/dev/sda2		10770	10777	64260		83	Linux
/dev/sda3		10778	11027	2008125		82	Linux Swap / Solaris
/dev/sda4		11028	14593	28643895	83	Linux

1 is Vista
2 will be /boot
3 will be swap
4 will be /

Now, when I enter 'v', fdisk tells me there are 12479 unallocated sectors. I know there is often a small amount of unallocated sectors due to different types of HD geometry or something like that, but 12479 seems outside the range of the normal "fudge factor".

The strange thing is, even though these are all 4 primary partitions, the MediaDirect button still manages to start the MediaDirect program (which promptly crashes) !!

Now, I learned from this site:
Understanding the Dell MediaDirect Partition

...that mediadirect has some super-hidden area at the end of the disk that most software can't touch. Perhaps that is the source of the 12479-sector discrepancy?
How do I recover this space? This is pretty important since this "feature" seems to trash my partition table whenever it is used.

Edit: the Gentoo installer reports a 1 MB unallocated space between sda1 and sda2 -- it also reports an unallocated space of negative 1 MB before sda1! WTF? The installer hangs a short way into copying files (might be a seperate problem)
Vista still boots fine.

[rcgreen]

You have a long road ahead of you. Since this computer severely violates
normal partitioning conventions, you will have to research it thoroughly.
Did you read the whole article? It's enough to make your head spin.

The way that might work is to leave this feature intact (or restore it),
and set up your dual boot without using the fourth primary partition,
since this is the partition it uses.

When the MediaDirect button is pressed, the extra LBA-3 code instructs the disk controller to expose the HPA, it temporarily swaps the MD partition descriptor into slot #4 of the real partition table, sets that partition active, and proceeds to boot the now active partition. When the computer is powered off or rebooted, the HPA and partition table return to their normal states.

Better yet, follow the link at the bottom of the page to a tutorial on
a linux dual boot with the Media direct feature.

HOWTO: mediadirect2 (all codecs) + winxp + linux - NotebookForums.com