2019 iMac's Fusion Drive User Upgrade

[Hexley]

I am getting the base model 27" 5K iMac with 1TB Fusion Drive. I know that it comes with 24GB of PCIe blade SSD + 1TB HDD.

If I were to do an after market upgrade by swapping out the 24GB SSD with an Apple 128GB PCIe blade SSD, will it work?

If I were to swap out the 24GB SSD with 500GB Samsung 970 EVO NVMe with adapter to Apple blade, will it work?

I read half a decade ago that Fusion Drive will not work with more than 128GB of SSD.

Looking towards 256GB M.2 NVMe SSD + 4TB 2.5" SATA SSD.

 

[Fishrrman]

It's not a very wise idea to go prying open a brand new iMac.
You'll instantly void the warranty, and if you break anything inside, it will be up to YOU to pay for the repairs, as well.

I believe the iMac blade is of a proprietary design. Not sure if they have adapters to match it to generic blade drives. Perhaps others will comment.

Best course of action:
- Either buy an iMac with an SSD pre-installed
or
- Get an EXTERNAL SSD (USB3 or thunderbolt3), plug it in, and set it up to be the boot drive.