It would be funny if two sets Apple RAM from two iMac 2020, running at 2133MHz on an iMac 2020.
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Memory upgrade troubleshooting in 2020 27-inch iMacs
- Thread starter KrazyKanuck
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Hmmm, given the reports of even identical sticks from the same manufacturers purchased at different times not playing nicely together, I think I won't bother ordering another set of the OWCs right away. I don't need more than 32GB right now and wasn't keen on outlaying even more cash straight away.
If and when it comes time to upgrade again I'll probably buy 4x32GB rather than rebuying 4x16GB sticks just to ensure they're from the same batch. Unless anyone has some luck running one pair in each channel?
If and when it comes time to upgrade again I'll probably buy 4x32GB rather than rebuying 4x16GB sticks just to ensure they're from the same batch. Unless anyone has some luck running one pair in each channel?
Heres a picture. The original 2x16GB worked at 2667MHZ no problem. I put the new ones into the remaining two slots and bam. I double checked the package same kit. Bought the same ones on amazon from the same supplier.
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I am going to try this tomorrow, see if I can call them and speak to someone I will report back what they say.
How did you get the info?
The Kingston I bought are 1Rx8
Are all of you with 2133MHz are of 1Rx8?
I'll post my story -
I started with the 3rd Tier and 8GB Ram (2 Apple 4 GB Sticks).... I purchased 2 16GB Sticks from OWC and had the same issues as everyone here - 9to5 way, 2667 but low Geekbench scores; "Normal" way and got the 2133 and higher scores.....
BUT - I purchased 2 additional identical 16 GB sticks from OWC and I have 4 slots filled with the same RAM size from the same manufacturer ...My results show that it WORKS.... (the second time I ran it I got 9000 for MS)
Like everyone here, I also was only getting 2133MHz when mixing with Apple RAM. I put in the Apple RAM into a Windows laptop and read the SPD data. My iMac came with Micron RAM. Looks pretty standard, it's odd that there's so much incompatibility. Hope this information helps someone find matching RAM.
You know, the more I think about this Max Tech video (and I must say that I'm not giving it too much thought), the more disappointed I am in him (and 9to5 as well). Here's somebody who's crafted an image of himself as striving to provide "neutral" advice, buying recommendations based on typical use scenarios, and benchmarks and comparisons that often split hairs on the differences between processors, graphics options, SSD speeds, etc. All in the name of buying efficiency: buy what you need, buy what's going to give you the best performance in your use case, buy this, buy that. But then he goes and suggests a workaround to the 2133MHz issue that drops dual-channel support. Neither Max Tech or 9to5 commented on this in the video. They effectively just say, "hey, look it drops to 2133MHz. That's strange." Whatever the cause of the 2133MHz, dual-channel is dual-channel and when you mix modules of different sizes in the same DIMMs it harms performance. Dual-channel isn't unique to the 2020 iMacs, so they should have at least been aware of this before pumping our endless videos pushing affiliate-linked RAM upgrades. The performance impact can be significant in many situations, certainly more than the difference between the i7 and i9, say, which Max spent so much time discussing. "Get the i9, but configure your RAM like this and it will perform like the tier-1 i5"
Compounding this is Max Tech and 9to5's unwillingness to acknowledge that there may be an issue to warn potential buyers of, or that their advice may be problematic. There are numerous comments on both videos (not by me, I swear! 😄) that articulately explain why the 9to5 memory configuration is a bad idea. Both channels themselves have "liked" videos posted before and well after these comments, and neither have addressed the issue by way of a comment or another video, which given the frequency that they upload, wouldn't be asking too much.
I realize that this isn't surprising to a lot of us on the forums, but for semi-knowledgeable buyers, even if they may not be fully impacted by the loss of dual-channel, it's just irresponsible advice. Given drewski_t discussion with Apple, it's pertinent to know that if you want to upgrade your RAM yourself you must be willing to discard and replace the Apple stock RAM, and whatever ungodly sum Apple charged you for it, instead of adding to it with compatible memory.
If you put the first pair in slots 1 and 2, and the second pair in slots 3 and 4, then for some unknown reason you should then get 2667 MHz and dual channel support. It defies expectations but that's what's happened with mine.
You don’t get dual channel. Geekbench scores reflect that. People who have done that to get 2667 MHz have seen multi score results between 5000-7000 with the 10910. When you configure it with dual channel but the speed is 2133 MHz the results are more appropriate at around 10,000.
I'm doing it, it's showing dual channel in CPU-Z in Windows, and I'm scoring 9000 in Geekbench in macOS on an i7.
Thanks for sharing your discussion with Apple. If this turns out to be the case, it's obscene. Why tinker with it in this iteration when simply adding RAM to the stock RAM worked fine before? What a waste of money for us to discard the Apple RAM, and what we paid for it, to upgrade ourselves and avoid paying their extortionate fees.
Interesting......
You're the only one so far in that config that have not seen a drop in scores.
Sorry, I've missed the earlier conversation. Are you running stock Apple RAM with 3rd party RAM and maintaining 2667 and dual-channel? If so, can you please specify again your particular configuration, brands, and capacities? Or point me to your earlier post?
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I'm doing what @gtosnipey was doing: not using Apple RAM, but mixing two types of third party RAM, which is why I told him to re-order them to maximise results.
Sorry to get your hopes up if you thought I was mixing Apple and third party.
It still shows that each stick does not have to be identical.
Evidence attached.
Attachments
Ah, you have the same size RAM. So that is why you have dual channel still.
The issue becomes is when you mix different size RAM. If you do 4 x 4 x16 x16 for instance, you will lose dual channel. To get dual channel back, you need to do 4 x16 x 4 x 16, but then you get the speed drop.
So your config will work with different brands/types of RAM if they are same size. Issue still remains if you mix RAM sizes. I was able to mix RAM sizes in my 2019 with no issues. So it’s curious what is the issue here.
It is strange that I got multi score at 6320 for my 10500 when in single channel, but just 5922 when in dual channel at 2133MHz.
But the background app is a bit different.
I’m not mixing two types of third party ram though. I bought the same 2x16GB kit from OWC twice on Amazon. Didn’t mix should all be the same?
You may just have been extremely unlikely. I did the same with my two pairs of Crucial, but fortunately they all worked together. My understanding is that each pair is tested as a pair to ensure compatibility. When you buy a package of four sticks, all four modules are tested together for compatibility. Compatibility cannot be ensured between two different packages of pairs, I think. Which seems kinda silly.
Put the sticks from the first kit in slots 1 and 2 and the sticks in the second kit in 3 and 4 and see what happens. This is very interesting to see how picky the 2020 iMac is.
But your system report is not reporting them as the same model or manufacturer.
They gave you two choices: purchase all 4 sticks from Apple (return the machine, upgrade ec.) or all 4 from a 3rd party. Since Apple is not the third party, what other choice are you expecting?
Ok, they didn’t document it but how does that affect your choices? Likewise, how is that bad customer service?
Crucial is the retail brand of Micron.
Could the real issue be mixing RAM sizes and not just brands? Has someone ordered two sticks of the latest Crucial the same size as the OE Micron and tested?
Oh please. Spare us the indignant rant. Compare the prices. Apple RAM has always been outrageously priced. In this case, it’s far less expensive to toss the 8GB of Apple RAM than other solutions if dual-channel performance is important to you. For many of us, it’s not; for others it is.
Apple gets to change their specs without your approval. Really, they do. We get the choice to buy or not buy. If you don’t like the situation, return the darned thing within 14 days or don’t buy at all. Vote with your pocketbook if you want to send a message—sometimes, it really is that simple.
In fact, if everyone bought these with 8GB only, could it have an effect on Apple’s future RAM prices or would they make this as difficult to upgrade as most other Macs? No one knows.
And you are the winner! So I just put the first pair in 1 and 2, and the second pair in 3 and 4, and they are now listed as 2667! Also, I am posting an image, the first two tests are in the original.
Also if you look at the ram, then are physically two completely different types of modules. I didnt compare them before I put them in I just assumed they were the same. They are not even though both from OWC.