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I’m upgrading my 1 TB Apple Fusion Drive on my mid 2017 iMac with a WD Blue 1 TB 3D NAND SSD. Do I need the inline thermal sensor too? All the questions and answers on here relating to the thermal sensor seem to be earlier than 2017 and SSD drives have moved on since then including the inclusion of SMART technology… Can anyone clear this up for me o CW and for all? THANK YOU?
It sounds like you are replacing the HDD part of the Fusion Drive set with a SSD. No, you don’t need the inline thermal sensor in your system. FYI: You still have the other part of the Fusion Drive the Blade SSD which is mounted on the other side of your logic board iMac Intel 21.5" EMC 2638 Blade SSD Replacement Frankly unless your HDD is failing I would replace the Blade SSD first. That way I can hold onto my stuff on the HDD and by setting the Blade SSD as the boot drive holding my Apps I will have a real screamer of a system! I would recommend going with a 480GB or 1TB drive. The bigger drive if you are composing music or editing videos. Make sure you use the correct tools (rotary cutter) and follow the iMac Intel 21.5" EMC 2638 Display Replacement guide to take off the display assembly. It’s very easy to damage it in the process of taking it off! Don’t forget the adhesive strips you might want to get a second set just in case!
You should not, but why use a fusion drive with an ssd (sata) drive in stead of an Nvme on the onboard dedicated slot that performs much better? You just need a cheap adapter in order to do this. by the way, in my experience you do not need any extra fancy gear to replace any thermal sensor. Update (03/08/2021) The fusion drive it’s a logical volume very prone to corruption so be careful. Best way to go should be a time machine backup followed by a fresh install of the os to the new disk and recover from TM backup. There are other options but I consider this the easiest to go with.
