Adding extra memory to a iMac (Retina 5K, 27-inch, 2017)
I just want to check this before I order memory (when it comes back in stock )
I've recently upgraded to a iMac (Retina 5K, 27-inch, 2017) which has 16GB RAM (2x8GB sticks), I was thinking about upgrading it to 32GB RAM, my last Late-2013 iMac had 24GB RAM and when running a Windows 10 VM and Adobe software it needed it.
My question is, with DDR4 memory, is it still necessary to install memory in matched pairs, i.e. another 2x8GB sticks, or will I still get the same performance adding one 16GB stick and leaving one slot empty?
Re: Adding extra memory to a iMac (Retina 5K, 27-inch, 2017)
The memory behaves the same way as your older iMac. Technically installing memory in pairs gives you the best performance, but most people will never notice it as it depends on the type of workload and even then you would only likely notice with benchmarks. You should be Ok installing mixed sizes unless Crucial mentions it "must" be installed in pairs.