I'm researching a memory upgrade for a 2018 Mac Mini (in advance of purchase). I thinking to buy it configured with the base 8GB and upgrade it to 32GB with aftermarket memory modules, at a savings of about 50% ($300) from the $600 extra of ordering it with 32GB.

The spec as far as DDR4 2666 MHz 260-pin SODIMM seems quite clear, but I haven't been able to find a CAS latency value for the RAM I'll find installed in the Mac mini. I wanted to get memory with a matching latency or perhaps something below. I'm not looking for extra performance; I just want to make sure it's as compatible as possible and not slow it down.

Here's the conundrum:

  • The Kingston and Crucial memory selectors both lead to CL=19 modules for Mac Mini 2018.
  • An offhand mention in an Amazon review stated that CAS latency for memory on iMac 2017 was CL=17.
  • Kingston offers HyperX modules (targeted toward PC gaming) that have CL=14 at a comparable price to the CL=19 modules.

So I was hoping to find an authoritative source for what the original-equipment CAS latency was for the Mac Mini. If it's CL=19 I'll go with the Kingston-recommended modules, but if it were CL=17 I'd probably go for the HyperX modules. Unfortunately, an hour of Googling around has met with no joy on that count.

Is there some place I can find that spec online or does someone just happen to know and could share that?

  • The Apple spec says Use Small Outline Dual Inline Memory Modules (SO-DIMM) that meet all of these criteria: PC4-2400 (19200) Unbuffered Nonparity 260-pin 2400MHz DDR4 SDRAM
    – Ruskes
    Commented Nov 16, 2018 at 4:55
  • Very interesting @Buscar웃, where can I find that spec?
    – scanny
    Commented Nov 16, 2018 at 5:59
  • here support.apple.com/en-us/HT201191#27inch2017
    – Ruskes
    Commented Nov 16, 2018 at 6:05
  • @Buscar웃 unfortunately that page is for the iMac and not for the Mac Mini. I did find a similar page for the Mac Mini 2018 but it does not mention CAS latency of the memory, only the DDR4 2666 MHz 260-pin SODIMM specs I mentioned in the OP.
    – scanny
    Commented Nov 16, 2018 at 7:18
  • As mentioned in the comment in mun's answer below, I did use Corsair's CL18 modules with Mac Mini 2018 successfully.
    – mato
    Commented Jan 25, 2022 at 8:33

1 Answer 1


Based on iFixit teardown which says these RAM pcs are Hynix model "HMA851S6CJR6N-VK" I'm assuming that they're the same as the ones you can find by browsing this model name (i.e. here) - and they're described as CL 19.

However, there's a video of this guy that switches his Mac Mini's RAM to CORSAIR "CMSX32GX4M2A2666C18" that has CL 18 and it seems to work fine.

  • Welcome to Ask Different! We tend to avoid link-only answers, as they decrease readability and are susceptible to link rot. Could you add the relevant pieces from the links to the body of your post?
    – JMY1000
    Commented Nov 26, 2018 at 20:58
  • I confirm CL18 works with Mac Mini 2018, I replaced RAM recently using Corsair's CMSA64GX4M2A2666C18 in 64 GB kit (IIRC) and all seems to work fine.
    – mato
    Commented Jan 25, 2022 at 8:30

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .