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I’ve completed the replacement of the HDD with a new SSD. I was aware that the Blade SSD existed but thought that it would simply appear as an extra storage device once the HDD was removed. Now I am seeing that there is apparently a procedure to get it working. Can someone explain how to do this or lead me toward a tutorial on how to do so? I have googled and not been able to find anything, mostly because I’m not really sure what I am looking for. Thanks in advance!
From what it sounds like you bought a Fusion Drive system which is why you have two drives the 3.5" HDD and a blade SSD. The size of the blade SSD is not very large. So while you can convert it from a cache drive to a readable drive it won’t offer much help. To get it working all you need to do is run Disk Utility and reformat it to GUID and a Journaled File System. Intro to Disk Utility on Mac