2667 mhz ddr4

Hi there dorriecs116,

We understand you'd like to install RAM in your iMac.

Learn more about which type of memory to use and how to do so here: Install memory in an iMac

We hope this helps.

Has this question been posted in the correct forum?

The iMac PRO uses DDR4 2666 Mhz ECC memory modules and the iMac PRO case does not have a user accessible RAM bay, the entire case has to be prised apart to access the memory slots.

i purchased 64GB of RAM from OWC. their specs indicate 2666MHz even though the apple documentation is 2667MHz is needed.

it works as expected in my 2019 27" iMac.

i forgot to add, under system report, it is recognized as 2667MHz.