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Recently, I purchased a Mac Mini 2014 A1347 model. I understand the RAM is soldered to the board and is not upgradeable. My next thought is to replace the HD and/or add a second HD. Currently, I am running Mojave on this computer and haven’t had any problems. I was thinking of at least installing a second drive but I am not sure if I need to buy a HD tray or HD cable. Update (05/20/2019) If I didn’t want to replace the main HD, can I add a second drive? If so, do I buy an HD tray or HD cable?
What is your current drive status? Mac mini Late 2014 SSD Replacement Mac mini Late 2014 Hard Drive Replacement UPDATE As you can see from the guides, adding an SSD is a 15 minute job while replacing the hard drive is a two hour job. Go here to select the size of drive to fit your needs: OWC Aura Pro X2 SSD
About your question. This unit is very much upgradeable when it comes to adding bigger or better hard drive. Only issue is its not as easy as just popping out a cover and pulling out the drive. To answer your exact question, this model comes with a regular mechanical drive and can be upgraded to a bigger size or even an SSD. You wont need any adapters or cables.