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I recently tried to replace the internal hard drive with a 1TB Crucial MX500 SSD but the iMac doesn’t recognise it when it’s connected internally. It doesn’t come up in Disk Utility at all. iMac is an 18,2 Retina 4k The original HDD still works when I connect it internally, so I know the cable isn’t broken. The new drive works fine in an external enclosure, so I know the drive is working. I plugged in an SSD from a different Mac and it works fine internally. Just not this new one, I bought the drive specifically from a Mac upgrade kit, so I assumed it should be compatible? Am I missing a setting for it? Firmware? Is there some kind of voltage incompatibility? I noticed the original drive is 5V 1.6A, the new SSD I have is 5V 1.7A. Could .1amp cause issues? Any help is appreciated, I’m going to buy another new SSD with a smaller capacity and see if that works
I bought another SSD, Crucial BX500, 960GB and it works perfectly! So, not sure what the actual cause was, but the MX500 1TB just wasn’t compatible
If you had a Fusion Drive’d iMac you first need to break the Fusion drive set Split Your Fusion Drive Apart As we don’t know which iMac you have you might have one that is using the older HFS+ file system and your new drive maybe setup with APFS. You will need to re-install the OS from Internet recovery or if you already have setup a Bootable OS installer with it (see note below!). Restart your mac pressing the Command (⌘) and R keys to enter into it. Make sure you’ve got a good connection to the internet. Reference: Mac startup key combinations Outdated image files If you have or plan to setup a bootable OS installer be aware Apple failed to maintain the certificates with the posted OS installer images If you’ve got an old macOS install image, it will probably stop working today Here’s the updated file images: How to upgrade to macOS SierraHow to upgrade to macOS High SierraHow to upgrade to macOS Mojave Jump to Step4 to find the image URL’s in all three. If you are using anything older you’ll need to cheat! As Apple did not update them ;-{ You’ll need to back date your system to be within the macOS’s window
