iMac Pro Samsung 980 pro NMVe - Has anyone successfully upgaded iMac 2019 to one of these

[Lemons69]

Im thinking of upgrading my iMac 2019 with a Samsung 980pro ... Has anyone tried this
If so what adapter did you use and did you use a heatsink ?

 

[ThunderSkunk]

I did use a 970 with heat sink, and the sink definitely fits in the enclosure, but OSX responded to the change of SSD extremely poorly, spitting out 8bit graphics and throttling the drive down to an unusably slow rate. OWC pointed out that if you never upgraded to Big Sewer and Monterey, you could safely boot from an external thunderbolt driveeven faster than the internal drive, and then just swap the internal drive for high capacity, slow speed storage. …but of course the changes to the firmware in B.S. & M, mean that after you “upgrade”, you risk the scourge of faulty EFI errors and destroying your SSDs if you try getting OS X to boot from other volumes. Apple really screwed us on that update.