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Both drives in my fusion drive failed. Have sent them off for data recovery, but am trying to save on the repair. I want to replace the fusion drives with only a single, larger-volume SSD. My hubs has experience building PCs, but we’re not sure what exactly needs to be done here. We’ve been confusing ourselves looking over guides like How can I switch from FusionDrive to SSD-PCIe only? one. Since both drives failed, do we still need to split them in Terminal? Can we even access Terminal if the computer currently has no drives installed? If we leave the flash slot empty and only replace the HDD with an SSD, is there anything else we need to do or will the Mac read the SSD just fine and ignore the empty connection?
Hold that thought! Fusion Drives are similar to a mirrored drive set. All of the data is on the HDD. The SSD holds the cached version of the files from the HDD (copies). It’s only if the file is altered and was not able to copy back to the HDD that the SSD might have something different (very rare). So… If the HDD is recoverable you’ll likely have everything maybe one file if the system crashed out just before the write action (a rare possibility). So you only need to ship the HDD for recovery. As you didn’t tell us what happened you might not need to go that far! Can you tell us what happened and what have you done so far. Update (07/29/2018) I’ve never had to deal with this exact situation so I’m not sure. So, lets look at this logically, the system does have a NV RAM chip which holds settings so I would assume if I reset it the setting would be lost. So I would do that before installing the drive. To do that you’ll plug in a bootable external drive and then do a reset with a USB wired keyboard. Here’s how: Reset NVRAM or PRAM on your Mac. As you’re installed a new drive any settings the Fusion Drive had are gone now. The rest of the task is just install the drive! Besides the SSD you’ll need a 2.5 to 3.5” adapter frame like: 2.5in SATA Hard Drive to 3.5in Drive Bay Mounting Kit we really only need the metal bracket and the screws. In addition to the frame you also need a in-line thermal sensor: OWC In-line Digital Thermal Sensor for Hard Drive Upgrade for 27" iMacs 2012 and Later It also has the needed display adhesive tapes. But! You will need some tools to take the display off without damaging it! Here’s what you need: iMac Opening WheelPlastic CardsiFixit Opening Picks (Set of 6) You still need a bootable USB thumb drive to boot the system and install the OS here’s how to do this: How to create a bootable macOS Sierra installer drive. You’ll note I’ve pointed to the Sierra setup I would recommend you still with this release until Apple fixes APFS when running on SATA drives, which hopefully is in this falls release.
I want to remove my fusion drive all together as well. Can I just leave it out and boot from a bootable thumb drive, or is there code you have to add in Terminal? Please list the steps I need to take. Thanks!
