Convert an Old Hard Drive into an External Unit


It’s quite common to have an old computer die on you and not have it repaired, especially if it’s more than a few years old. But what can you do with the old carcass? 

If a computer dies for any reason other than a dead hard drive, you can always convert the old drive into an external unit, and grab important files off the drive in the process. The same thing can be done if you install a larger hard drive in your computer and don’t know what to do with the old one.

The first thing you should do before investing any time and money in an old hard drive is to try to determine if it’s ok. If your old computer was working fine and then died all of a sudden, the hard drive is most likely fine. Motherboards, power supplies, microprocessors and memory can fail in the blink of an eye, but hard drives usually become flaky, make strange sounds or exhibit other errors before they die. If your hard drive seemed fine before the system died then it’s probably OK.

Likewise, if your system was working fine and you simply swapped the old hard drive for a bigger one, then the old one should still be just fine. We won’t get into the details of upgrading a hard drive because it’s a very complicated process. But the easiest way to upgrade is to use hard drive cloning software or hardware that lets you duplicate your original hard drive on a much bigger, blank hard drive. Once duplicated, you simply swap out the old drive for the new one. Otherwise, you can simply install a new hard drive in your computer and format it from scratch. Of course, you’ll need the discs for the operating system, all the drivers and utilities and all of your applications, along with the corresponding serial numbers where required.

Getting back to creating an external hard drive, the next thing you need to make certain of is the size and type of drive you have. Notebook computers typically use 2.5-inch hard drives, simply because they’re smaller and use less power than 3.5-inch desktop hard drives. If you’re not sure what size your drive is you can measure it. Hard drives have a rectangular shape, and the smaller of the two sides is where the size is measured.


Next, you have to determine what kind of drive you have because you need an enclosure that’s compatible with your drive. Older computers contain PATA, or IDE hard drives, and newer ones contain SATA hard drives. The connectors on PATA hard drives consist of a double row of metal pins, while the connectors on SATA hard drives consist of two flat tabs.

You need to buy a hard-drive enclosure that matches the size of the drive you have; a 2.5-inch enclosure for a 2.5-inch drive and a 3.5-inch enclosure for a 3.5-inch drive. Keep in mind that 2.5-inch enclosures are usually bus powered, meaning that they pull power from the port they’re plugged into and they don’t come with a power adapter; this makes them completely portable. On the other hand, 3.5-inch hard drives need more power than can be pulled from a computer port, so the 3.5-inch enclosures usually come with an AC power adapter and they are not portable—meaning that they won’t work if there’s no AC outlet available.

Now you have to decide what kind of interface you want on your hard-drive enclosure. Most drive enclosures feature USB or FireWire interfaces because they’re the most popular ones in use, and some feature a combination of both to make them more versatile. Most USB enclosures are USB 2.0, which is compatible with any USB port out there. But only USB 3.0 peripherals will deliver USB 3.0 performance, and that’s only when connected to a USB 3.0 port. More and more new computers feature USB 3.0 ports, so you might want to go with a USB 3.0 enclosure.

Installing a hard drive in an external enclosure is very easy; usually all you need is a screwdriver. In the worst case, you might have to move or remove a jumper that sets the drive to be a master or slave, but the odds are you won’t have to touch anything but your screwdriver. 

Once your external drive is working, you can connect it to a computer and pull any files you want from it. Then you can format the drive and start with a clean slate. If you are uncertain and feel as though you might need the assistance of professionals, contact the B&H computer service center.

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Why would a 250 GB data drive only show 107 GB of space after this process? Great article thanks.

That shouldn’t be the case. Even when taking into account the difference in math that hard drive companies use, and computers, you should have about 230GB of space available, after it is formatted. If you didn’t format the drive, it still contains all the information that it previously had when it was installed in your system.

My laptop died and I was given the hard drive out of it (mother board failed) and have turned it into an external hard drive. In order to get the maximum benefit from my new drive, should it be formatted to erase all of the data that is currently on it?

I would assume that I should back up anything I want to save, right?

Hi Ev -

Formatting this re-purposed drive would be your best approach.  Backing up the existing data would be recommended as well.

Please contact us via e-mail if you have additional questions:

I have a 3.5 inch Seagate Barracuda HDD (SATA) ... Will this product work with that ?! [P.S. I have no knowledge on computers] :D

Yes, that enclosure will work without any issues with your drive.

My old laptop died on me and I just order an enclosure kit. Will I be able to clear the newly converted hard drive by plugging it into my new laptop? I want to delete everything off it and use it as an external hard drive but I am afraid their might be viruses on it and they may be transferred when connecting to my new laptop?

You will be able to format your old drive, and use it as an external on a new system. If you think that there is a chance that there is one or more viruses on the old drive, I would highly recommend that you update (or install) your antivirus software before you plug it into the system. Once the drive is formatted, all information, potential virus’ included will be erased.

I recently bought an external enclosure for my PATA drive from an old laptop, but it's not communicating with my new PC (I've used both windows 7 and 8 OS). It powers up just fine.

The 4 pins on the side of the main row have nothing connected to them, and I think I need to put a jumper on it to designate that it's either a slave or master drive. Am I correct in thinking this will solve the problem? If so, which should I designate the drive as (with the physical jumper)?

Thanks in advance :)

This would depend on the make, and model of drive, as well as the requirements of the enclosure. In most cases you would need to set the drive to master. If you look at the top of the drive, it may have the pin-out. If not, look at the circuit board, it may have MS and SL for master and slave. If you still cannot get the drive to mount, please take photos of the drives top, bottom, and pins, and send them to, along with the model of enclosure you purchased.

I have a very old IDE hard drive that I connected to a 3.5" Mobile Disk enclosure. When I turn on the power supply it powers up but when I plug the USB into ANY computer nothing happens. I have tried Mac OX, Windows XP, Windows Vista and Windows 98. Nothing works, I don't know what I am doing wrong. Is it possible there is something wrong with the disk drive, or can it be too old? It worked just fine when I took it out of my old PC.

Using an older IDE drive in an enclosure usually requires you to set the drives jumper to CS (Cable Select) or MS (Master.) If you have already tried both settings, it is very likely that you have either a defective drive, or enclosure.

I removed two 250GB hard drives from an old Gateway computer. I would like to purchase enclosures to convert them to external hard drives. Both drives are Hitachi Deskstar SATA Model: HDS722525VLSA80. Will the following product work with these drives?

Yes, the Macally T-S350SU enclosure will work for your drive without any issues.

I have an old 80gig hd.It's from an even older pc. But now I have my lap top and the old hd has a ton of music I don't want to lose. Will the tutorial I just read work for my situation?

If you have a hard drive with connection older than PATA (IDE) I would recommend sending an e-mail to with as much information about the drive as possible.

i have two drives one pata and one sata. but what i dont understand is they are both 4 width on 6 length so what case do i get. also is there such a thing as a duo case, also for pata and also for sata, or maybe a double case one with pata annd the other sata or something like that.

The two drives you have are both referred to as 3.5” drives. (Not the smaller 2.5” size) We do have enclosures that will work with both SATA, and PATA drives that size, however we do not have a single enclosure that will house both at the same time.  The two compatible enclosures can be found here.

I do have a PATA (IDE) Hard drive and I want to buy an Enclosure to make it an externall HDD and also to recover my old files from the HDD, my PATA HDD do have a OS installed on it's C: drive. is that ok?

Having an operating system on an older, external drive is not usually an issue. To prevent any potential problems, either disable USB booting on your computers BIOS, or simply wait to turn on / plug in the drive until your new OS has loaded.  

I do not want to format my old hard drive because I have so many pictures and important documents on it. I want to use it as an external backup, and would like to clear as much unnecessary stuff off to make room.   Is it possible to get the Windows and Program folders off? It was a Windows 7 OS. When I try to delete the folder it says I need permission to perform this action. I have gone into security settings and set the files to Full, but it still will not let me delete them.

If deleting the folders is not working for you due to permissions I would recommend copying all of the documents you want to keep to another drive. Once you have backed up the files you want to keep then you can format the external drive. Once the drive is formatted you can move your files back over.

(Make sure you do not forget any files as once you format anything left behind is deleted.)

Good Afternoon             

I have a Dell Inspire Model M5030 purchased November 2010, the laptop has been service twice.  Both times in January 2011.  Motherboard was replaced; the system has crashed again last week. Black screen with the seven continuous beeps.   The hard drive was operating alright before the crash.  My question is: is it possible for me to remove the hard drive from the laptop, and convert it to an external drive. What type of devise do I need to purchased, and where can I buy one.  I did check with Best-Buy and they said I could not, which did not make any sense to me until I was advised that for $130. I could have the data transferred  onto a new system. 

That computer uses a standard 2.5” SATA drive, and as long as the drive it’s self isn’t damaged, you should be able to insert it into an enclosure like the Kingwin 2.5" USB 3.0 SATA Hard Drive External Enclosure (  and retrieve your data on an alternate system.

I need to remove the HD from my laptop and make it into an external drive due to the screen is screwed up and not covered under warranty. Due to the information stored on my HD I would like it to be able to be accessed by my new laptop. My old laptop is a Dell Inspiron 15.6" laptop. I believe as you said above it would be a 2.5 inch enclosure but I don't want to buy it and be wrong. Any help you could give would be appreciated.

The enclosure that you would need would depend on the drive type. Please contact us via e-mail ( with additional information, including the full model of the Dell Inspiron laptop that you are removing the drive from.

My laptop crashed and I got the hard drive from it and an IDE External Hard Drive Enclosure. When I plugged it into my PC it tells me that the drive needs to be formatted, but I need to get the data first! What can I do?


It appears that when your laptop crashed, it may have been due to the hard drive, or another failure could have corrupted the drive. In either case, data recovery is needed. Unfortunately, we do not offer this service, or carry recovery software. Runtime software is currently offering an experimental Live Data Recovery CD at no cost. ( I highly recommend trying this first. If you are unable to retrieve your files, bringing your drive to a local service or data recovery center would be the next step. See if they offer a free estimate as data recovery can be costly.  

Dear Sir/Madam,

I pulled out two 1TB Seagate HDDs from the dead CPU. The drives bear the following code : Barracuda 7200.11

The size is 4 inches by 6 inches.

can I find a suitable enlosure and power supply to convert these to external HDD as they have my important data 

The Sabrent ECS-STU35K USB 2.0 ( will work for both 3.5” SATA, and IDE drives. It includes everything you need to install the drive, including the screws,  a screw driver, and power supply.

Dear Team,

How could we get it?



Orders can be placed on the website and by phone.

800.606.6969 / 212.444.6615

I have about 12 Sata hard drives, any suggestions for what to do with them.

If you plan on getting rid of the drives, you can use a degausser ( to bulk erase the drives. This will prevent any personal information from getting into the wrong hands.

If you would like to use the drives, a dock ( would let you use them like an oversized floppy disk. The StarTech USB 3.0 to Dual 2.5/3.5" HDD/SSD Docking Station uses USB Attached SCSI Protocol to provide additional speed on supported computers, and the drives are hot swappable.

Another great option would let you connect all of your drives and create one large volume that can be accessed on your network. The Drobo B1200i 12-Bay NAS Storage Array (