How to build your own external hard drive on the cheap

By Rich Edmonds
last updated

Having an external hard drive at hand is an ideal way to not only store and transfer files but also back up a PC.

Portable HDD
Portable HDD

Having the latter handled by online cloud services is all well and good, but should you lose connectivity, or the service goes down temporarily, you will not have immediate access to your files. When it comes to external drives, it's also possible to not only purchase one pre-built, but you can also make one yourself.

We'll show you how to save some pennies by putting together your own external hard drive, using an old laptop drive.

Choosing storage

Portable HDD

Should you wish to purchase an internal drive separately, it's possible to choose a 2.5-inch HDD with your choice of capacity. And 3.5-inch drives are better suited for larger storage solutions that don't require portability.

Depending on just how much space you require from a drive, it's possible to spend as little as $40. Here are some options:

Solid-state drives (SSD) are not recommended due to the cost. Also, should you need more than 1TB of space, you may want to look at a 3.5-inch drive. Already have the drive to spare? All you'll need is an enclosure to create a capable portable unit.

Enclosing the drive

Portable HDD

With a 2.5-inch drive ready to go, you'll need an enclosure to secure the drive and allow for the transfer of files between the disk and a PC. Here are some affordable options:

Depending on which enclosure you purchase, the drive bay may require a screwdriver to attach the drive to the casing. Other, more expensive options usually come with some sort of mechanism that allows for toolless installation and removal of drives. Once the drive is installed, it's then possible to connect it to a PC and format it for storage.

Rich Edmonds
Rich Edmonds
Senior Editor, PC Build

Rich Edmonds was formerly a Senior Editor of PC hardware at Windows Central, covering everything related to PC components and NAS. He's been involved in technology for more than a decade and knows a thing or two about the magic inside a PC chassis. You can follow him on Twitter at @RichEdmonds.

6 Comments
  • This is great, you guys should do more of these.
  • I would be careful about ventilation. I bought an external 6TB 3.5" hard drive and there was *no* ventilation in the case at all. The drive generates a lot of heat, and it actually damaged the tiny circuit board in the case that interfaced with the SATA connector on the drive and turned it into a USB connector. I kept getting drive disconnect error messages, forcing me to remove the case and buy a USB to SATA adapter. Try to find a case with some serious vents on it or something
  • 6tb in a single usb case???
    That's a NAS enclosure hdd lol... to be used in Raid etc. To be honest if you want to go down that route, even with vents it won't be enough. You will need a active hdd cooling solution, you can buy them for a few bucks - most use molex for power connectivity. I have one for an old Pata hdd, used to heat up like crazy.
  • I've got a 1tb Seagate 3.5 drive in a SATA/USB enclosure made by Rosewill which has a 2 speed fan for cooling built in. Works fine and came with all the cables and connections for any type of hookup. Got it off Amazon. My only complaint is the enclosure has no quick release for removing or installing the drive.
  • It's not a bad idea to have more than one that you normally keep disconnected to store backups, because ransomware. It can target any attached backups, so having it unattached takes care of that. And since ransomware isn't immediately apparent [it takes time to do its thing], it's quite possible that it's busy encrypting your stuff while you're copying it to a backup external drive, &/or that your backup includes the malware, so more than one USB drive for backups is cool. If you do plan on lots of sustained data transfer to/from an external drive, Do Not forget cooling. Without sufficient active cooling a 3.5" drive can get hot enough to potentially damage your data if not the drive itself. With older versions somewhat frequently given away, Hard Disk Sentinel will let you keep tabs on the temps for your external drive. Also research reviews & such, &/or test, because the on-board USB electronics can start to fail at sustained max data rates for 20 minutes or longer. While it's a bit rare nowadays, if you can use a eSATA drive housing or dock, you'll get higher data transfer rates than USB or via your network. If you use a SSD for your external drive, look for a housing that supports UASP, though it works better with 10 than 7, if/when compatible drivers are even available for 7. It's MUCH faster than regular USB 3. If/when portability isn't an issue, consider a drive dock, though if you use a small [5-6"] USB desk fan for cooling they can take up a bit of desk space. That way, with the exception of the drive or drives, you're only paying once for the hardware.
  • Best Buy is selling a WD 4 TB external hard drive for $80 which is probably cheaper than anything you can build yourself.