In most cases, the answer is a resounding yes. In fact, I’ve done it myself.
However, there are a few caveats to be aware of.
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Inside that external hard drive is an internal hard drive.
Most external hard drives are simply standard hard drives in a box with an additional circuit board that converts their native interface to USB. Depending on the drive, there might be an external power supply, or “brick”. So yes, open the case and you’ll likely find a standard hard drive you can then install directly into your PC.
Things to watch for
There are a few things to be aware of before you crack open that box, however.
- Doing so instantly voids the manufacturer’s warranty. After you break the seal and open the box, you’re on your own.
- Be sure it has the correct interface. Most computers and drives now use the SATA interface, but if you have an older computer or drive, you might be faced with an IDE interface. The two are not interchangeable.
- Make sure the physical size of the drive matches what your computer can use. This normally limits you to 3-1/2-inch drives, though some computers accept 2-1/2-inch drives. If you’re installing into a desktop machine, there may also be mounting converters you can use1.
- It probably won’t be one of your faster drives. My expectation is that drive manufacturers use their slower drives in external boxes. Drive speed is typically not a limiting factor when placed behind a USB interface, and slower drives also run cooler, reducing the need for an external drive to include powerful cooling fans, or perhaps any fan at all.
When to consider
Moving an external drive into a PC is generally done as a convenience. There’s one less external box to deal with, and the drive will probably operate faster internally than across a USB interface.
There’s one additional scenario worth considering: external drive failure. More specifically, if an external drive fails, it could either be the disk drive itself, or it could be the USB conversion circuitry. I’ve had the latter happen, and rather than discarding a perfectly good hard drive, I simply installed into a machine.
A note about data preservation
A you move hard drives from external enclosures to an internal installation (or vice versa), the formatting and contents will likely be preserved. I’ve done this a time or two, and in each case, the data on the hard drive was preserved and immediately available in its new configuration. In fact, data recovery is one of the major selling points for doing the reverse of what you’re asking — taking the internal hard disk of an otherwise broken machine and installing it into external enclosure.