Many users’ first reaction to a slow and old computer is replacing the hard drive with a new one or with a SSD. Some people also choose to buy a new computer for a better experience. Either way, your old hard drive will be put aside. When buying an enclosure for converting HDD to USB, you should take 2 things into consideration: interface and size. The interface and size of the enclosure to buy must match that of your hard drive. Please don’t throw the old drive away; it is still useful. Making old HDD to USB is a more economical and environmentally friendly choice. It only takes surprisingly little effort for you to convert internal hard drive to external USB. HDD to USB: A Better Way to Dispose Old Drive If the hard drive was used in a desktop originally, it’s possible that it has a PATA interface and 3.5 inch size. At this time, you should look for a 3.5” enclosure that gives support to PATA/IDE.

If the hard drive is taken out from a laptop, it’s possible that the interface is SATA (there are also a small number of laptop hard drives equipped with an IDE interface) and the size is 2.5 inch. Therefore, you need a 2.5” SATA enclosure.