# How to wipe a hard drive clean



## 1nf3rn0x (Mar 25, 2014)

I'm going to be selling one of my desktop's soon and wanting to wipe both harddrives completely clean so that no information or data can be retained. Never done this before, so anyone willing to give me a simple guide?  Thanks


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## flmatter (Mar 25, 2014)

right click on drive and select format.   free and easy    there is software out there that may do better. free is still good.  if you have an install disc you can delete/format the drives that way too. Just stop the install process when computer restarts after deleting partitions and formatting.


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## arskatb (Mar 25, 2014)

http://www.dban.org/
if u want something much better try
http://www.blancco.com


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## RCoon (Mar 25, 2014)

1nf3rn0x said:


> so that no information or data can be retained


 
SecureErase. It's a built in firmware command for all HDD's, you can run it from a Live boot CD liked Parted Magic. Nothing else will wipe it properly unless it's a high powered drill.


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## HammerON (Mar 25, 2014)

RCoon said:


> SecureErase. It's a built in firmware command for all HDD's, you can run it from a Live boot CD liked Parted Magic. Nothing else will wipe it properly unless it's a high powered drill.


Using it (them) as target practice with a nicely powered shotgun, pistol or rifle will also work


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## Drone (Mar 25, 2014)

I use killdisk One zero-pass is enough


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## FordGT90Concept (Mar 25, 2014)

Drone said:


> I use killdisk One zero-pass is enough


Same but I use DoD 5220.22M 3-pass with 40% verification.  It does a pass of zeros, a pass of random data, and then the opposite of the random data.  Verification makes sure the values that are read from the drive match what it wrote.



RCoon said:


> Nothing else will wipe it properly unless it's a high powered drill.


Correction: metal shredder.  NSA allows 5220.22M for secret data but any drive that contained classified data needs to be shredded.  Drilling it would stop an amateur from retrieving data but it doesn't stop professionals.


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## Jetster (Mar 25, 2014)

Just formating will not erase the drive. But there are a bunch of free programs that will. Killdisk is just one. Now a SSD drive is another matter

Its going to take hours to secure erase the drive


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## JunkBear (Mar 25, 2014)

If I really want to destroy a HDD I just remove the cover and start it with a psu. Then I use 40 coarse sandpaper to grind the disk inside. Work like a charm and I guess it will oprevent even professionnals from reading.


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## n0tiert (Mar 25, 2014)

just get yourself a Ubuntu Live CD and use this cmd in prompt

dd if=/dev/urandom of=/dev/sda bs=1M


where "/dev/sda" describe your drive, _sda_ is usually the first hard drive.

free and easy to use

EDIT: like jetster already mentioned, it takes time depends on HDDrive size


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## natr0n (Mar 25, 2014)

any low level format tool will work


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## Sasqui (Mar 25, 2014)

natr0n said:


> any low level format tool will work



LOL!  I saw the thread title and thought the same thing.


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## FordGT90Concept (Mar 25, 2014)

JunkBear said:


> If I really want to destroy a HDD I just remove the cover and start it with a psu. Then I use 40 coarse sandpaper to grind the disk inside. Work like a charm and I guess it will oprevent even professionnals from reading.


You do realize the data is magnetic, right?  I suspect sandpaper doesn't distort the magnetic fields.



n0tiert said:


> EDIT: like jetster already mentioned, it takes time depends on HDDrive size


capacity / sequential write speed

Examples:
3,000,000 MB / 150 MB/s = 20,000 seconds or 5.5 hours per pass
40,000 MB / 60 MB/s = 667 seconds or 11.1 minutes per pass


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## Ahhzz (Mar 25, 2014)

I +1 the dban. Plus the name is cool  . Most of the above posts are correct all over the place (excepting the one about "format"). One of the mentioned free softwares will do the job well, but for NSA standards, obviously more is involved. All of the options short of melting it will take extended time to perform, or materials you may not have access to, but I gather you want to send the drives *functional* with the computers, so you're down to software. I recommend a single pass with killdisk for simple protection, or if you're selling to a techie or really worried about the data, run dban several times 

In addition, check the post here, specifically the section regarding "Zero Fill a Hard Disk", which points to free software provided by the hard drive manufacturer.


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## newtekie1 (Mar 25, 2014)

FordGT90Concept said:


> You do realize the data is magnetic, right? I suspect sandpaper doesn't distort the magnetic fields.



It would destroy the coating on the platter, which would destroy the data.  Though it sounds to me like the OP wants to actually keep the drive usable.  So another vote from me for DBAN.  Though I use the PRNG Stream Method.


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## 95Viper (Mar 25, 2014)

flmatter said:


> right click on drive and select format.   free and easy    there is software out there that may do better. free is still good.  if you have an install disc you can delete/format the drives that way too. Just stop the install process when computer restarts after deleting partitions and formatting.





Ahhzz said:


> Most of the above posts are correct all over the place (excepting the one about "format").



Actually, if the OP is using Windows Vista or better, flmatter is correct.

Quote from About.com PC support pages:



> _Format_
> The format command has had a */p* option since Windows Vista which acts as a basic data sanitization tool, performing a write zero on each sector of the drive as often as you specify (e.g. *format /p:8* for eight full write-zero passes). In fact, the */p* option is assumed unless you perform a "quick format" using the */q* option.
> In Windows 8, however, the functionality of the */p* switch has changed in an important way. In Windows 8, any number specified is _in addition_ to a given single write zero pass. Furthermore, each additional pass overwrites with a random number. So while *format /p:2* in Windows 7 would overwrite the entire drive with zeroes twice, the same command executed in Windows 8 will overwrite the entire drive with zeroes once, then again with a random number, then again with a different random number, for a total of three passes.



Screen shot of Windows 8.1 "format /?"


Spoiler


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## FX-GMC (Mar 25, 2014)

95Viper said:


> Actually, if the OP is using Windows Vista or better, flmatter is correct.
> 
> Quote from About.com PC support pages:
> 
> ...



I didn't know they had changed that.  Nice.


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## n0tiert (Mar 25, 2014)

if he want´s to sale the rig why make such work installing windows to use format or other application ?
and from within windows formating main drive ? dooh

all other will lead to attach 2nd hdd with windows or plug that drive into other PC

just use simple ubuntu live cd ......


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## FX-GMC (Mar 25, 2014)

n0tiert said:


> if he want´s to sale the rig why make such work installing windows to use format or other application ?
> and from within windows formating main drive ? dooh
> 
> all other will lead to attach 2nd hdd with windows or plug that drive into other PC
> ...



He should be able to run the format option from a Windows install cd.........

AANND maybe not.  Seems you may have to be in the install process to get to the command prompt.  I'd just use a DaRT disk to do it, though I'm sure many people haven't taken the time to make one.


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## Ahhzz (Mar 25, 2014)

In addition, check the post here, specifically the section regarding "Zero Fill a Hard Disk", which points to free software provided by the hard drive manufacturer.


95Viper said:


> Actually, if the OP is using Windows Vista or better, flmatter is correct.
> 
> Quote from About.com PC support pages:
> 
> ...


Thanks for the info, didn't know that   Altho, the paranoid in me says "The NSA is in everything M$ does. Are they really writing random, or a pre-generated set of data that an encryption key will reverse?"


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## eidairaman1 (Mar 25, 2014)

http://www.killdisk.com/downloadfree.htm


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## 95Viper (Mar 25, 2014)

n0tiert said:


> if he want´s to sale the rig why make such work installing windows to use format or other application ?
> and from within windows formating main drive ? dooh
> 
> all other will lead to attach 2nd hdd with windows or plug that drive into other PC
> ...



Yes, I don't believe you can format the system drive from within windows.
If you have a need to wipe the system drive... they would need to make a system repair disk; or ,as known in windows 8/8.1, a system recovery disk.
As far as I understand, windows 8 can make a DVD or a USB drive system recovery; however, Windows 8.1 can only make a USB drive one.
But, you can, also, use the 8/8.1 install disks to boot into the repair options. (if you have them or obtain the ISOs and create them)
They can boot to any of those options and use the command prompt with the proper format command and attributes to format and over-write any drive.


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## Arctucas (Mar 25, 2014)

+1 to Secure Erase.

However, if you are selling the PC without an operating system, why not sell it without the drives entirely?

The new owner will need to install an OS, and a new HDD or SSD is not exactly prohibitively expensive these days...


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## Disparia (Mar 28, 2014)

I like to do just a simple 1 pass. Whether you're in Windows or Linux there is a tool to do it built-in and if someone was going to pay for the services needed to recover data after one pass, they could just give me that money and I'll give them the drive intact. That'll save the buyer some time and net me a few thousand dollars.


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## 1nf3rn0x (Mar 28, 2014)

I went over them with boot and nuke 3 pass


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## Neo Jensson (Mar 30, 2014)

You can use DBAN, ErACE, etc. They will over write whole hard drive. So it is impossible to recover data with any recovery tool


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## johnspack (Mar 30, 2014)

Delete partition,   recreate partition,  reformat.  That will deal with a lot of it,  but 256bit or higher dod wiping is best for the paranoid,  but really over the top for most uses.


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## Aquinus (Mar 30, 2014)

I have to agree with @n0tiert , disk destroyer (haha) is probably the best free tool to use imho, however I wouldn't use /dev/urandom or /dev/random as they add overhead, /dev/zero would probably be faster.

```
sudo time dd bs=1M if=/dev/zero of=/dev/sdx
```


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