Spreading the word, I got higher than 32gb working installed on my 2013 27in.
With Catalina it will probably work on 2013-2015 Imac's
My wife has had a "Late 2013 27in Imac" for 6 years and does print design on it 24/7. It's been getting long in the tooth and I've upgraded it over the years with an SSD and added 32gb of ram a few years ago which it regularly maxes out through Photoshop. We were debating getting something new...
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