Recovering files from a overwriten HD - Impossible except on TV? :P

Hey Everyone,

If you overwrite a hard disk with random data, is it possible for a data recovery firm, FBI, Government, etc, to get anything out of it? Or is that all just part of general TV fiction?

I'm not an expert in Data recovery techniques so before I outright dismiss this, I figure I might as well ask for that 0.1% chance that it might be possible.

 

To be safe, overwrite it multiple times with something like DBAN. And unless you were holding nuclear launch codes and the location of Osama, you're probably safe.

 

To be sure, do a low level format of the hdd from 3 to 5 times.

 

:flamethrower:Burn it.

 

So what's the deal? Do you need to write several passes because the software itself for overwriting is not accurate enough to do it properly the first time? Or is there some residual effects that the data leaves behind which can still be detected unless you sufficiently wear it out by successive writes?

 

There is residual, left over magnetic that makes previous data recoverable.

By overwriting the HDD several times (and with specific patterns, not just random data) those residual magnetic traces are more or less "erased", finally wiping the data that once was stored on the HDD.

 

So a hard drive can theoretically store 3 or 4 times it's actual rated capacity through this 'residual' data?

 

Nah, not really.
The effort one needs to pull to get any usable results from that is too high.
That's why you pay (at least) four digit prices when a recovery company attempts to recover data in those cases.

Hmm.... lol?.... maybe....?

 

LMAO

 

Seconded. If you're that worried about the content being found just physically destroy the disk beyond recognition an buy a new drive. It's gonna cost you a pretty penny for decent wiping software anyway.

 

screw around with it with magnets and take it apart if you really want to destroy it. The HD is a vacuum and when you open it allows air into it.

 

A HD is definitely not a vacuum. At least all the ones I've seen. They have vent holes that specifically say do not cover.

 

Parts inside are. If you open a part inside it it lets air in killing the HD

 

No, it's not a vacuum. It is dust free, the breather holes are so it can equalise the internal/external pressure.

You can open a HD and it won't die, you can even run it when it's open but the dust in the air will probably make it unhappy quite quickly. Although it will still be mostly readable.

Hard drives store digital data on an analogue media, which is why you need to overwrite them multiple times. You can tell the difference between something that was zero and has been changed to a one & something that has been written as a one multiple times.

After a couple of random writes there is nothing left apart from the randomness.

 

Thanks for the clarification. So what is it that makes the clunking sound when Hard drives go bad? i was under the impression when air was in it the platters moved about clunking.

 

You could just throw it out? lol