Fusion Drive to SSD
I'm planning to remove the Fusion Drive from the iMac 5K and replace it with a Samsung 512GB SSD + upgrading the Apple PCIE SSD to 512GB.
Is that possible?
Thanks in advance :)
Model A1419 / EMC 2806 / Late 2014 or Mid 2015. 3.3 or 3.5 GHz Core i5 or 4.0 GHz Core i7 (ID iMac15,1); EMC 2834 late 2015 / 3.3 or 3.5 GHz Core i5 or 4.0 GHz Core i7 (iMac17,1) All with Retina 5K displays
I would think long and hard here before attempting this. First these systems are a bear to open! Many people have damaged their displays in the process in these newer 'Thin Series' iMacs. If you do attempt this make sure you have the right tools and have a few sets of adhesive strips (in case you need to reopen).
OK, lets hit the different things you have here:
Larger SSD's are not presently available from Apple and so far no 3rd parties that offer upgrades are offering SSD upgrades for the newer 'Thin Series' iMac's. I should also point out you need to completely remove the logic board to even gain access to the SSD socket. Here's the IFIXIT guide as a reference: iMac Intel 27" Retina 5K Display SSD Replacement.
Before you do this you need to break the Fusion Drive set first as if you replace the HD the blade SSD it was mated to will re-establish a Fusion set with your new drive (which you don't want to do here). You also want to make an external bootable USB thumb drive with the OS installer so you can reformat and install a fresh OS on your SSD.
Follow this IFIXIT guide on replacing your HD: iMac Intel 27" Retina 5K Display Hard Drive Replacement. In this case you'll need an adapter cable to replace the thermal sensor the HD has as the SSD doesn't have one that is accessible to the system heat management system (SMC). OWC offers the needed part: OWC In-line Digital Thermal Sensor for Hard Drive Upgrade for 27" iMacs 2012 and Later.
To be honest here. You may want to think about selling your iMac and jumping up to a Mac Pro system if you want this level of power and more! It's a lot more serviceable and expandable both internally and externally.
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