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ethan870

macrumors newbie
Original poster
Mar 28, 2022
6
0
Hi guys.

I currently have a 2017 27 IMac 4.2 with 1TB Fusion Drive and 32gb RAM.
I am always working with Lightroom and Photoshop for work and I noticed that my Fusion Drive now cannot perform anymore.

I just purchased a Crucial BX500 2TB and a Samsung NVme 970 Evo Plus 1TB

If I upgrade both SSDs can I install the OS and apps on the Nvme and restore onto my Crucial only files and documents from Time Machine ?
Thanks
 

Fishrrman

macrumors Penryn
Feb 20, 2009
29,175
13,223
A fusion drive doesn't have "two SSDs".
The one you have has a 1tb platter-based hard drive and a 32gb blade SSD, "fused" together using software to make it appear as if it's "one" drive.

You realize that Apple uses a "proprietary design" for the connection of their internal blade SSDs?
And that an off-the-shelf nvme blade SSD won't fit?

Do you feel competent enough to take the iMac apart and do the work, and get it all together again, without breaking anything inside during the process?
This IS NOT "a trivial procedure".

An alternative suggestion:
Leave the fusion drive alone.

Instead, get a USB enclosure like this for the Crucial:
Connect this to the iMac's USB3 port.

For the Samsung nvme, get a USB3.1 gen2 enclosure (many available).
Connect THIS to the iMac's USBc port.

Set the Samsung up to be the new boot drive.
Connected to the USBc port, you should get read speeds around 850MBps or faster.

Use the Crucial drive as a data drive. It should give you reads in the 420MBps range.

Leave the internal fusion setup "in place, not used".
It can become a bootable backup (you ALWAYS ALWAYS ALWAYS want to have A SECOND bootable drive "within arm's reach")
 

ethan870

macrumors newbie
Original poster
Mar 28, 2022
6
0
A fusion drive doesn't have "two SSDs".
The one you have has a 1tb platter-based hard drive and a 32gb blade SSD, "fused" together using software to make it appear as if it's "one" drive.

You realize that Apple uses a "proprietary design" for the connection of their internal blade SSDs?
And that an off-the-shelf nvme blade SSD won't fit?

Do you feel competent enough to take the iMac apart and do the work, and get it all together again, without breaking anything inside during the process?
This IS NOT "a trivial procedure".

An alternative suggestion:
Leave the fusion drive alone.

Instead, get a USB enclosure like this for the Crucial:
Connect this to the iMac's USB3 port.

For the Samsung nvme, get a USB3.1 gen2 enclosure (many available).
Connect THIS to the iMac's USBc port.

Set the Samsung up to be the new boot drive.
Connected to the USBc port, you should get read speeds around 850MBps or faster.

Use the Crucial drive as a data drive. It should give you reads in the 420MBps range.

Leave the internal fusion setup "in place, not used".
It can become a bootable backup (you ALWAYS ALWAYS ALWAYS want to have A SECOND bootable drive "within arm's reach")
Thank for your replay.

I do appreciate your concern and I know how delicate is to work with iMac especially with the screen but I opened many iMacs in the past and I am very confident about it but I do appreciate.
I know that Fusion Drive cannot have two SSDs, I already dismounted the current Fusion Drive and I now see both the HDD and the 32GB SSD.
My question was about setting up the drives as I will install the OS on the Samsung Nvme ( I already have purchased a Sintech ST NGFF2013 with Kapton tape ). I have many other external SSD but I prefer having the full speed of the Samsung internally at 2500+ MBps.

All I wanted to know was how can I (after installing the fresh OS on the Samsung Nvme) only restore files/documents and not the entire OS on my other Crucial SSD which will be used for Data and plugged internally using a Mounting Bracket?

Thanks for your help
 

Fishrrman

macrumors Penryn
Feb 20, 2009
29,175
13,223
There's no need to "refuse" the new SSDs.
Just format and set them up as separate, independent drives.

The nvme will run the fastest that way, in any case.
 
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