Recovering Secret HD Space

An anonymous reader writes "Just browsing hardocp.com and noticed a link to this article. 'The Inquirer has posted a method of getting massive amounts of hard drive space from your current drive. Supposedly by following the steps outlined, they have gotten 150GB from an 80GB EIDE drive, 510GB from a 200GB SATA drive and so on.' Could this be true? I'm not about to try with my hard drive." Needless to say, this might be a time to avoid the bleeding edge. (See Jeff Garzik's warning in the letters page linked from the Register article.)

Comments

Re:Floppy / Drill fun

[innocent_white_lamb]

THIS method is obviously BS (to put it mildly) but back when the dinosaurs roamed the earth we could double the size (or was that 1.5x, I can't remember) of a MFM hard drive by hooking it up an RLL controller. I remember putting a full-height IBM 10mb hard drive into my 386 and making it into either a 15mb or 20mb hard drive. I used that hard drive to store and rotate Fidonet echomail for several years, as I recall.

That worked because RLL encoded the data using a different method than MFM.

This, though, is smoke and mirrors.

Andre Hedrick

[Anonymous Coward]

The old Linux IDE guy spoke of something like this a while back. Apparently the drive vendors got sick of stocking every drive model for warranty replacement, and implemented a scheme where they could "flash" a generic drive with a specific model number and capacity. Therefore it's possible that your "120GB" drive is really qualified for 160GB but was set that way for inventory reasons.

This was on the linux-kernel list a while back, too lazy too find it. (And it's possible I misunderstood -- Hedrick is a crackpot who is barely able to articulate what he is thinking.)

Re:How? Reliability?

[Blastrogath]

It seems to work by deliberately corrupting your partition tabes by overlapping your patitions:
Partition a from 0 to 200 GB
Partition b from 1 to 200 GB etc.

You could probably get it to say almost any amount, but it wouldn't be usable space.

Some drives may have a little extra space but not 70 GB on a 80GB drive. No sane company is going to sell a 150 GB drive as an 80 GB because they pay as much to manufacture platters and heads no matter how they're used. The cost of the unused parts would come right out of their profits. Also, sometimes there is "unused space" used for the hard drive's bios, or for relocating data from bad sectors.

Anyone remember NaBob?

[PCM2]

(I post this here because maybe you've been around long enough to remember when ARC vs. ZIP vs. LZH vs. some others was a big deal.)

Back in the days of the "archive format wars" somebody made a program called NaBob that was pretty funny. It made archives that were so perfectly compressed that they approached singularity. That is, every archive turned out to be one byte long.

The various compression methods, it was said, were named after different types of quarks. So, as the files were compressed, it would report, "upping," "downing", "charming," "stranging," etc.

The file extension was .BOB.

When you ran the uncompress process, all your files would be mysteriously "extracted" from the archive again. Amazing! It really stored all that data in a single byte!

Of course, all it was really doing was setting the hidden file bit on all your files and creating a one-byte file with the .BOB extension, but hey, as they say, there's one born every minute.

That program always cracked me up, so I just thought I'd share.

Re:Floppys used to be better..

[Geekbot]

I'll second that. Wish I had a mod point for you. I don't trust 3.5s any more at all. USB flash drives for quick mobile storage, CD-Rs for anything bigger or more long term. Even the CD-Rs don't last well anymore. Now all those 3.5s come with those stupid little plastic sliders instead of the sturdy old metal ones. Constantly I find those things coming off and getting jammed in the drives at work. And the plastic is so cheap and flimsy they are almost a real "floppy" disk again.
Of course, it doesn't help that now it's not just the computer geeks using these things and a bunch of stupid college kids are storing all of their term papers on these crappy things. Then they run around with them jammed in their back pocket or backpack until crushed, bent, or otherwise destroyed.
My job involves me helping people use the computer, but I'm about to put a sign up that help with college work will cost extra.

Re:Uh, no

[Shanep]

Sorry, but this is complete bullshit.

Yes. I call it corrupting your partition table. ; )

Years ago, when an 800MB drive was "big", a friend of mine tried to convince myself and a group of IT staff friends, that he could get around BIOS limits of a particular DEC workstation, through some tricky settings of the geometry in the BIOS. LBA was not big in those days and MS OS were still using the BIOS for disk access beyond the boot process.

Anyway, my friend managed to "trick" the BIOS into seeing 800MB (previously 504MB).

So, in an attempt to prove him wrong, I then proceeded to format the drive. MS-DOS format claimed it was formatting the drive as 800MB, but this did not deter me. I knew that MS-DOS was simply fooled into thinking that 800MB was actually addressable on that particular (504MB through BIOS limited) machine.

The format completed fine! But I was still not detered. I said, "ok, now we start to fill this drive up...".

I started copying a large directory over and over to fill the drive. When we approached about 500MB... "Seek error: sector not found.". The drive no longer booted either.

What had happened, was that we managed to force the BIOS to accept geometry values which it could not fully address. Most Significant Bits which MS-DOS would send, would never get seen by the drive, since the BIOS could not go beyond a certain address width. So while formatting, MS-DOS would be sending write commands which would be honored by the drive, but the BIOS would be passively stripping some of the highest MSB's out of shere lack of support of them.

The end effect, was that at the 504MB point, the drive head would be about 504MB's in to the 800MB, then at 505MB, the address would go back to zero and the head would come back to the start! That first sector would be formatted again, the drive would report success, and MS-DOS format would think nothing of it. When it got to "800MB", it would have all appeared to format ok to MS-DOS.

The end result was an 800MB drive, with a partition table which that BIOS was never going to be able to fully service, even though MS-DOS format "saw the proof" that all was fine. ; ) When someone tried to copy data to the next "safe" sector beyond what the BIOS could address, what they were actually doing was writing back over the beginning of the disk! Corrupting the partition table.

; )

I was delighted, because everyone else was on my friends side, even though one of my buddies also had a background in electronics and should have known what I was talking about. Anyway, modern drives DO have secret areas set aside for remapping of bad sectors (to give you the consumer the perception of zero bad sectors and all the space you legally purchased), but this space is way smaller than what these jokers are claiming and it is normally not user accessible.

So, save yourself the hassle of wondering in a few months time, why your drive has "crashed". You might not remember the "magic" that you did to your drive.