Yesterday Apple released a new version of the Mac Mini that no longer features user-servicable RAM, but thankfully the new iMac with Retina 5K display still allows users to upgrade memory through an access door on the back, just like previous models. The new machine houses four memory slots.
Apple’s BTO Prices
If you want to upgrade your memory, you can get 16 GB of DDR3 1600 MHz RAM for $136.50 (about $30 off) at Amazon (below). The kit comes with two 8 GB modules, meaning you can grab two of these kits for a total of 32 GB for around $270. Not a bad deal at all, given that some outlets are charging just under $400 for the same memory—never mind the comical $600 Apple is asking. (Comical in that the 1st 2x8GB kit costs $200 and the second one costs $400 more :/)
The Crucial RAM at Amazon (or other upgrade kitss that are around) will also give you 2 extra 4GB Sims which you can sell or keep in case of emergency.