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macrumors newbie
Original poster
Jul 9, 2018
Hi all. I purchased my 2018 Mac Mini a few months ago with the base 8GB RAM, with the intention of upgrading myself when the need arose.

That time has now come - I only get about half a day before the swap starts rising - but I am tossing up between purchasing 2x 8GB chips and upgrading to 16GB, or for a few extra dollars buying just one 16GB chip and replacing one of the current 4GB chips, for a total of 20GB.

I've always heard that you should used matched pairs, but wanted to double check with the MacRumors brains trust the pros/cons to 16GB vs 20GB in the 2018 Mac mini.


macrumors G3
Nov 23, 2011
If you feel like taking the time to do a search, there are several existing threads on this question that cover the pros and cons.

In that time you could’ve answered the question or even linked to one of these several threads, rather than giving a smarmy reply.

In answer to the OP: I’m honestly not sure. I tend to match pairs of RAM wherever possible but I’m not sure if that’s superstition or good habits. There certainly were some benefits to matching RAM in the past but I can’t say for certain if that’s the case now.
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Nov 2, 2018
The memory is dual channel. With unmatched pairs, it won't perform at its full performance potential.

However if you intend to add another 16GB stick in the short to medium term (i.e. in 2019) you may get some benefit from the increased memory albeit at slower speeds, until you can buy the second one.
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Oct 31, 2017
I would recommend purchasing just the single 16GB module. As mentioned above if the processor supports dual channel then matching modules will result in the fastest access to memory. However such performance is likely to go unnoticed in anything but benchmarks and applications which are sensitive to memory latency (if you don't know what this means then you don't have to worry about it). It's better to have the correct amount of memory than faster memory. In addition purchasing the 16GB module means you don't have to discard any of the new memory should you want to move to 32GB.


macrumors 6502a
Sep 14, 2011
Leeds, UK
For cost in the short term get a single 16GB stick, that will run the RAM unmatched, so a little performance loss in speed but a greater amount of RAM overall so you'll get less memory swapping with the SSD/page outs etc. Then later in the year pick up another 16GB.

I'm looking at an i5 2018 Mini and the 16+4 route is the way I was thinking of going.


macrumors 603
Sep 8, 2011
Agreed, get the 16GB DIMM. It'll be slower, but not so much that you'd notice it - and it gives you the future expandability to just add another 16GB stick to get to 32GB, without trashing what you've already bought.
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