Hey Rich! I just had a heck of a time trying to upgrade my SSD in my 2019 27” iMac. Turns out the 1TB WD Black and the 1TB 970 PRO NVMe’s didn’t work in mine, still not entirely sure why.
However! The 970 EVO 2TB and the Sintec NVMe Macbook air 2013 adapter worked flawlessly with an internet restore boot option.
I also upgraded to a retail i9 9900k and everything works flawlessly!
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