Chosen Solution
Hi I am waiting to upgrade my iMac 5k FUSION DRIVE-SPECIFICALLY THE 24G PCIe SSD in motherboard and not the SATA 3 HD drive(why not get more bang for my bucks /performance) I realize its a risky major teardown and also don’t want to use an external SSD with thunderbolt as this negates the reason i love an iMac My question is can i use the new samsung NVMe 960 EVO M.2 SSD? From what i can tell its also a 4 lane based PCIe SSD? Can i use it?
Sorry guys ;-{ Apple uses a custom SSD drive. Here’s a good reference: The Ultimate Guide to Apple’s Proprietary SSDs Now lets dig a bit deeper here. A Fusion Drive is made up of two drives the slower SATA disk drive and a fast PCIe/AHCI drive. The reason was to offer faster SSD access by caching the more heavily access data. In truth Apple is only copying the data from the HDD to the SSD. If the data is updated it’s written to the HDD so the data is not lost. OK, so does it make sense making the SSD larger than what Apple installed? You hit a few issues as the more you cache the more re-writes are needed to keep it updated. This causes the SSD to wear quickly. The SSD Apple is using is really a 128 GB drive its just that a very large part of it is held in reserve! Which is why it’s listed as only 24 GB in size. What I do is forget the Fusion Drive config and just setup a dual drive setup. Here the wear issue is much less! I try to get my customers to go with a 256 or 512 GB blade drive. The SSD is setup as the boot drive (OS) and all of the apps. I leave the rest of the drive empty! The reason for this is the OS and the Apps need free space for caching and paging which we do want to run off of the SSD. The HD is then the bulk storage of the data. The only issue with this setup is if you are doing large image, video or music work. Here you may need a still larger SSD I’ve seen people install 2 TB drives in the newer iMac 5K systems. So what is your needs? Will going with a dual drive config work for you?
Hi Dan, My Fusion Drive in my 27” iMac 27 late 2014 (3TB) is failing. I’m about to replace it. The problem is making sure of the drives that are compatible with this iMac. I’m thinking about replacing the blade SSD for a 1 or 2TB and, if the HDD is ok I can use it as a second drive to folders, documents, etc. I think the problem is with the SSD of the Fusion Drive set, as all the apps are very very slow and re-formating didn’t solve the issue. I work with video, with 4k rate heavy files, so I need performance and speed. What would be your advice? I’m going to follow your tutorials to replace the drives. Thank you
