Did I order the incorrect memory?

Kilobyte Kid

Did I order the incorrect memory?

Hi there.

I have purchased a new iMac Retina 5K, 27-inch 3.4GHz Intel Core i5, 2017 and have decided to upgrade the ram to 32gb, so I placed an order directly with you.


My order was for part no. CT10559858 however upon further investigation, I think I've ordered incorrectly and  should have ordered CT10559878 instead, but I'm not sure (my order no. is 0604685724).


Did I order the wrong part? And are you able to advise if CT10559858 is OK to use in my mac? I don't want to have to return it if I don't have to.




1 Reply
Community Manager

Re: Did I order the incorrect memory?

@stevro25 Thanks for contacting us today. It appears that you did order the 32GB kit for your system.  If you purchased the iMac with the standard 8GB adding the 32GB to it would actually allow you to upgrade to 40GB of RAM as you can mix the RAM. CT10559878 is a 16GB kit. Adding this kit to 8GB of standard RAM would give you 24GB of RAM. Both kits are completely compatible it will just depend on how much RAM your system came with originally and if you mind having more than 32GB of RAM or not Smiley Wink Please let me know if you have any other questions or concerns or if there is anything else I may be able to help you clarify. 

YogiH, Crucial Moderator, US

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