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I have a RAM question.

Is it better to get a single 32 gig stick (so I have the option of later on adding another one if it seems it's needed), or two 16 gig sticks?
2x16 GB to benefit from dual channel.

In fact, buying RAM in paired sticks is always better because of that reason, whatever the capacity.
 
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Just to be clear: If I buy 2 of these 2x HyperX RAM blocks, they should be OK to use in an iMac 2020?

Totally useless to buy this RAM. Please refer to first post for 100% compatible part list.

I have 4x16GB (two of the kits linked) of these running perfectly fine in the iMac 2020. Always used HyperX in my Macs, always been a great success!
 
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So aside from it being a generic/off brand company... whats the opinion on these for a total 128gb setup?


should i just get the crucial and save $2000 over apple instead of $2200 lol
 
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So aside from it being a generic/off brand company... whats the opinion on these for a total 128gb setup?


should i just get the crucial and save $2000 over apple instead of $2200 lol
Lol. I would’t touch that. It’s even pricier than Crucial RAM (in canada at least). Don’t do that.
 
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A question guys - should I boot up and get everything set up with the usual 8GB, or can I swap out for me 32GB kit before I even turn the iMac on for the first time?
 
A question guys - should I boot up and get everything set up with the usual 8GB, or can I swap out for me 32GB kit before I even turn the iMac on for the first time?

I’m planning to set it up first and then put the new RAM in. That way I eliminate the RAM as being a possible source of issues if I run into any.
 
Confused about Crucial's part numbers vs their "Configuration IDs":

Back in June I bought and returned the newest Mac Mini model. I had purchased the following 32 GB Crucial card to go with it, but forgot to return it to Amazon in time:

Crucial 32GB DDR4-2666 SODIMM Memory for Mac, Part #: CT32G4S266M, Configuration #: CT19038861

Now that I am about to order a 2020 iMac, I'm wondering if I can use this same card. The part number (CT32G4S266M) is listed in the compatibility list further up the thread, but when you run the 2020 iMac through Crucial's memory selector the same card comes up, but with a different configuration ID:

Crucial 32GB DDR4-2666 SODIMM Memory for Mac, Part #: CT32G4S266M, Configuration #: CT19090528

The specs look exactly the same. Is it the same? What exactly does Crucial's configuration ID represent?

Also, even though the compatibility list above says the 2020 iMac requires PC4-21333 speed memory, both configurations of this chip are listed as PC4-21300. Do those 33 MB/s make a difference?
 
Confused about Crucial's part numbers vs their "Configuration IDs":

Back in June I bought and returned the newest Mac Mini model. I had purchased the following 32 GB Crucial card to go with it, but forgot to return it to Amazon in time:

Crucial 32GB DDR4-2666 SODIMM Memory for Mac, Part #: CT32G4S266M, Configuration #: CT19038861

Now that I am about to order a 2020 iMac, I'm wondering if I can use this same card. The part number (CT32G4S266M) is listed in the compatibility list further up the thread, but when you run the 2020 iMac through Crucial's memory selector the same card comes up, but with a different configuration ID:

Crucial 32GB DDR4-2666 SODIMM Memory for Mac, Part #: CT32G4S266M, Configuration #: CT19090528

The specs look exactly the same. Is it the same? What exactly does Crucial's configuration ID represent?

Also, even though the compatibility list above says the 2020 iMac requires PC4-21333 speed memory, both configurations of this chip are listed as PC4-21300. Do those 33 MB/s make a difference?
It’s the same. It’s probably only an index in their system to find the correspondence between RAM modules and Mac model. It will work.
 
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Confused about Crucial's part numbers vs their "Configuration IDs":

Back in June I bought and returned the newest Mac Mini model. I had purchased the following 32 GB Crucial card to go with it, but forgot to return it to Amazon in time:

Crucial 32GB DDR4-2666 SODIMM Memory for Mac, Part #: CT32G4S266M, Configuration #: CT19038861

Now that I am about to order a 2020 iMac, I'm wondering if I can use this same card. The part number (CT32G4S266M) is listed in the compatibility list further up the thread, but when you run the 2020 iMac through Crucial's memory selector the same card comes up, but with a different configuration ID:

Crucial 32GB DDR4-2666 SODIMM Memory for Mac, Part #: CT32G4S266M, Configuration #: CT19090528

The specs look exactly the same. Is it the same? What exactly does Crucial's configuration ID represent?

Also, even though the compatibility list above says the 2020 iMac requires PC4-21333 speed memory, both configurations of this chip are listed as PC4-21300. Do those 33 MB/s make a difference?
I think the configuration ID is tied to the model of computer, whereas the part # is the specific card.
All this means is that CT32G4S266M is compatible with both the Mac Mini (represented by config CT19038861) and the 2020 iMac (represented by config CT19090528).
I think. I am not a Crucial dude.
 
Thanks for the quick response. Also for saving me $160 (for now) and/or a miserable call to Amazon customer support. 👍

It’s the same. It’s probably only an index in their system to find the correspondence between RAM modules and Mac model. It will work.
 
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I really need 32gb of Crucial to come back in stock at Amazon. I've got a gift card burning a hole in my pocket.
 
Just installed my HyperX RAM, and so far so good. It is reported as Kingston memory.
Screen Shot 2020-08-31 at 10.45.25 AM.png
 
@pldelisle I have to purchase my RAM from Amazon. Should I wait until the Crucial is back in stock, or just go with the Kingston?
 
Nice. Did you see the origin of the chip on the chip itself ? I think HyperX is usually either Hynix or Micron DRAM chips.

Both of mine are Micron. Ordered 2 sets a few weeks apart directly from Kingston (HyperX). Same part number as ZBoater.

Hoping ZBoater does some Geekbench!
 
So, I've read through all of this and I am still a bit confused about a few things.

(1) If I buy 32GB (2 x 16) of memory (replacing the original 8 GB) and later decide to buy another 2 x 16 to go to 64GB, am I likely to have an issue? Do I have to buy the same brand?

(2) If I understand, if I have 2 sticks of 16GB they have to go in slots 2 & 4 or 1 & 3 in order to keep dual channel. But if mixing 2 kits of 32 GB (for a total of 4 x 16 GB sticks) it looked from Wilberforce's test that the best results come from putting 1 kit in slots 1 & 2 and the other in 3 & 4? Is that right?

(3) Apple uses different memory suppliers. Some people are getting RAM manufactured by Micron. Can the 8GB Apple RAM using Micron be combined with third party RAM without reducing RAM speed?
 
A question guys - should I boot up and get everything set up with the usual 8GB, or can I swap out for me 32GB kit before I even turn the iMac on for the first time?
Just received my iMac and pulled out the 8GB of Apple ram and installed 32GB from OWC (2x16GB) before ever plugging the machine in and had zero issues...
 
If I buy 32GB (2 x 16) of memory (replacing the original 8 GB) and later decide to buy another 2 x 16 to go to 64GB, am I likely to have an issue? Do I have to buy the same brand?
I’d upgrade directly to 64 GB. You have to pick the same brand and same capacity for all your memory modules. It also have to be the same DRAM chip manufacturer. With Crucial and Samsung it’s more easy than the others since you know it’s going to be Micron or Samsung chips. Not the same for OWC which buy DRAM chips from different manufacturers.
If I understand, if I have 2 sticks of 16GB they have to go in slots 2 & 4 or 1 & 3 in order to keep dual channel. But if mixing 2 kits of 32 GB (for a total of 4 x 16 GB sticks) it looked from Wilberforce's test that the best results come from putting 1 kit in slots 1 & 2 and the other in 3 & 4? Is that right?
Modules are in pair in slots 1-3 and 2-4. Don’t mix. Rule #1.


Apple uses different memory suppliers. Some people are getting RAM manufactured by Micron. Can the 8GB Apple RAM using Micron be combined with third party RAM without reducing RAM speed?
You need to discard the Apple modules. I’ve seen no experiment showing a working dual channel and full memory speed with Apple stock RAM and aftermarket. Resell the memory modules to someone having a 2019-2020 iMac that have the exact same chips in it to ensure it will function properly.
 
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