I went to Microcenter yesterday to just inquire about RAM upgrades. Found out they don’t put the RAM in unless it’s the official Apple RAM and he quoted me around $450 for 16GB. But the guy said to do it myself that it’s very easy as he’s done a bunch of them. They don’t sell the 2666 but they sell the 2400 and he said to get that, it will work. But I didn’t buy it because it says 2666 and n my Mac. Would 2400 work and would I see any problems, figure I would ask on here before I looked into it.