Memory upgrade troubleshooting in 2020 27-inch iMacs

[Mr. Warbles]

I am in same boat. Got 2x32gb Samsung installed and working great. Though I want to fill other 2 slots, I don't see real valid reason as I couldn't stress memory more than 28GB in my used case.

Yeah I guess that's what I'm wondering. Will Logic Pro X, Adobe CC & Rendering in after Effects stress the system beyond 64GB? Would 128GB be better or not necessary? I don't ever really do any of those things simultaneously. Usually just one at a time.

BTW, unrelated but how do you like your iPhone 11 Pro Max? Thinking of picking one up (Smaller one not the Max) since some good deals are starting to pop up and will likely continue with the 12 Around the corner. I don't need the newest phone just want those sweet camera's and I don't want to pay over $1000.

 

[jacklivehere]

Yeah I guess that's what I'm wondering. Will Logic Pro X, Adobe CC & Rendering in after Effects stress the system beyond 64GB? Would 128GB be better or not necessary? I don't ever really do any of those things simultaneously. Usually just one at a time.

BTW, unrelated but how do you like your iPhone 11 Pro Max? Thinking of picking one up (Smaller one not the Max) since some good deals are starting to pop up and will likely continue with the 12 Around the corner. I don't need the newest phone just want those sweet camera's and I don't want to pay over $1000.

Keep us posted how do see real life situation with memory (with 64gb)

Iphone 11 pro is great btw, you won't regret it. But if you are with T-mobile or AT&T wait for 3 more months and get 5G iPhone. I think its worth the wait due to low band/Midband 5G.

If you are with Verizon, go ahead with 11 pro.

 

[wilberforce]

Has anyone tried the Timetec branded RAM from Amazon? It uses HYNIX chips, and is "made for MAC," and might be more compatible with the Apple RAM (also HYNIX chips). I am thinking of trying some, but won't bother if someone else has already tried without success. (I usually use Crucial.)

 

[propower]

Same experience here with OWC 32GB. Took the 8GB Apple RAM out and put the 32GB OWC in the slots where the Apple RAM was - got 32GB at 2667MHz. Will stress test for a few days and report back if anything goes awry. Did notice that the RAM cover didn't fit right after - turns out a few of the metal spring contacts around the edge were either defective or bent out of shape - will call Apple tomorrow about that...

 

[jacklivehere]

Same experience here with OWC 32GB. Took the 8GB Apple RAM out and put the 32GB OWC in the slots where the Apple RAM was - got 32GB at 2667MHz. Will stress test for a few days and report back if anything goes awry. Did notice that the RAM cover didn't fit right after - turns out a few of the metal spring contacts around the edge were either defective or bent out of shape - will call Apple tomorrow about that...

metal spring contacts are not high quality. I have same experience as you . Never had this issue with previous iMacs

 

[DQ11]

Mine is supposed to arrive August 25th...I'm thinking of just ordering 32gb more from OWC so I don't have to worry about it...I paid for 16gb of apple ram I'll never be able to use.

 

[pldelisle]

Has anyone tried the Timetec branded RAM from Amazon? It uses HYNIX chips, and is "made for MAC," and might be more compatible with the Apple RAM (also HYNIX chips). I am thinking of trying some, but won't bother if someone else has already tried without success. (I usually use Crucial.)

Where did you find it uses Hynix DRAM ?

Usually, these cheap brands use whatever DRAM chip is cheaper when ordering a batch. They rarely stay on the same manufacturer.

Mixing origins for RAM is always tricky. Mac or not, motherboards don't like that. Running same-vendor modules is always the best option.

 

[wilberforce]

Where did you find it uses Hynix DRAM ?

Usually, these cheap brands use whatever DRAM chip is cheaper when ordering a batch. They rarely stay on the same manufacturer.

Mixing origins for RAM is always tricky. Mac or not, motherboards don't like that. Running same-vendor modules is always the best option.

The description in amazon says TIMETEC -HYNIX and they arrived yesterday and have “Hynix” printed on the chips. My iMac has not arrived yet so cannot test them.

 

[pldelisle]

The description in amazon says TIMETEC -HYNIX and they arrived yesterday and have “Hynix” printed on the chips. My iMac has not arrived yet so cannot test them.

I tend not to be confident with Amazon's description on such precise things

You might have been lucky.

 

[PBG4 Dude]

Hey guys, got a new 8 core iMac coming and 64GB of Samsung RAM sitting here. I’m going to ditch the 8GB of Apple RAM to get the most out of it.

Now I’m thinking of just getting another 64GB just to max it out to 128GB but do you think it will be a noticeable difference for me?

I mainly use my computer for recording and mixing audio, graphic design (Adobe CC), and simple editing in After Effects.

thanks!

Max Tech did a video where he examined the effects of different amounts of RAM which you may find helpful.

 

[NewUsername]

After watching this video I am only more confused about the slot configuration:

In fact I'm now so confused I'll just replace the two Apple modules with the two Crucial modules and keep the Apple modules in a box… 32GB is overkill for me anyway. (I have 8GB right now and I am almost perfectly happy with that.)

 

[KrazyKanuck]

After watching this video I am only more confused about the slot configuration:

In fact I'm now so confused I'll just replace the two Apple modules with the two Crucial modules and keep the Apple modules in a box… 32GB is overkill for me anyway. (I have 8GB right now and I am almost perfectly happy with that.)

The 9to5 video made an unfortunate suggestion to mix different sized RAM modules in the same DIMM to restore 2667 MHz speed. Max Tech echoed these instructions, and now I'm sure there are many users who are unknowingly hindering the performance of their new machines by throttling their memory bandwidth. If you have two 4GB models and two 8GB modules and you mix them in the same DIMMs (ie. 4GB and 8GB in DIMM 0 and 4GB and 8GB in DIMM 1), you're effectively halving your bandwidth when you reach capacity in the 4GB modules, which is worse than going from 2667 MHz to 2133 MHz. At least this is what I've come to understand.

 

[quagmire]

After watching this video I am only more confused about the slot configuration:

In fact I'm now so confused I'll just replace the two Apple modules with the two Crucial modules and keep the Apple modules in a box… 32GB is overkill for me anyway. (I have 8GB right now and I am almost perfectly happy with that.)

I have 8 GB sticks( Apple OEM) in slots 2 and 4 and 16 GB sticks( OWC) in slots 1 and 3 in my 2019 iMac. Both running full speed. I am also keeping dual channel config.

So what the video says is misleading and not necessarily true in how you want to configure different sizes of RAM sticks. I would want to think this is a software bug when mixing RAM sizes then anything else. Or there is some kind of hardware difference in the RAM sticks causing the slow down. We shall see though.

 

[KrazyKanuck]

I have 8 GB sticks( Apple OEM) in slots 2 and 4 and 16 GB sticks( OWC) in slots 1 and 3 in my 2019 iMac. Both running full speed. I am also keeping dual channel config.

So what the video says is misleading and not necessarily true in how you want to configure different sizes of RAM sticks. I would want to think this is a software bug when mixing RAM sizes then anything else. Or there is some kind of hardware difference in the RAM sticks causing the slow down. We shall see though.

Yes, it seems to be an issue with these 2020 iMacs specifically.

 

[quagmire]

Yes, it seems to be an issue with these 2020 iMacs specifically.

I would want to lean software bug because when they are configured correctly by keeping dual channel, Geekbench scores are reflecting what these CPU's should be scoring around. You would think a ~500 Mhz slow down on the RAM would also effect the scores or is my lack of knowledge of how Geekbench works starting to show?

 

[Fred Zed]

The 9to5 video made an unfortunate suggestion to mix different sized RAM modules in the same DIMM to restore 2667 MHz speed. Max Tech echoed these instructions, and now I'm sure there are many users who are unknowingly hindering the performance of their new machines by throttling their memory bandwidth. If you have two 4GB models and two 8GB modules and you mix them in the same DIMMs (ie. 4GB and 8GB in DIMM 0 and 4GB and 8GB in DIMM 1), you're effectively halving your bandwidth when you reach capacity in the 4GB modules, which is worse than going from 2667 MHz to 2133 MHz. At least this is what I've come to understand.

In one of max techs latest videos about memory upgrade of a 2020 iMac. Towards the end of the video if you pause the video it shows 2017 iMac about screen. again another reviewer rushing out videos for views.

 

[KrazyKanuck]

In one of max techs latest videos about memory upgrade of a 2020 iMac. Towards the end of the video if you pause the video it shows 2017 iMac about screen. again another reviewer rushing out videos for views.

Another day on the content farm spraying manure to reap a harvest. It's a shame, because I generally like Max Tech and I like 9to5. But the trend toward daily re-reviews is an unfortunate one, but necessary, I suppose, to grind out a living from YouTube.

 

[Spk1]

I initially bought 2x8 sticks of RAM from OWC, but after having gone through this thread, I bought another pair of 8GB sticks again from OWC, though this time through Amazon because shipping from the States is very slow. Haven’t got the iMac yet but I’ll put the first pair in slots 1 and 3, and the second pair in 2 and 4 and I should then get dual channel at 2667, correct? Or is there some caveat I missed?

 

[Azrael9]

Yes. I'm just running on the Crucial right now. It's stable and at 2667 MHz.

Running on Crucial. 2667 Mhz. 40 gigs. (32 gigs Crucial. 8 gigs Apple. 2 sticks each.)

Azrael.

 

[redlik]

Same situation as you. Sticks arriving tomorrow, mac not until 2-9 September :-(

 

[cinnamongirl96]

Looks like I'm in the same boat as everyone else. Had a 2019 iMac on order and planned to do the 8GB+32GB upgrade that was so popular for those models - never came into stock and changed my order to the 2020.

I've just put in 2x16GB OWC modules - tried alongside the Apple RAM initially and had the same 2133 result as everyone else - glad I saw this thread today otherwise I'd be wondering what I'd done wrong! Removed Apple RAM and now running happily at 2667. Found the springs in the RAM door to be pretty touchy, I was very careful to apply even pressure and still managed to bust a couple of them (never done a memory upgrade before so not sure if this is usual) - it's sitting nicely now though. I didn't bother to swap the order of the sticks as I figured my results would be the same as everyone above - I'd rather just have 32GB running optimally right now.

I'm now wondering whether I should order another set of the OWCs straight away. I don't need 64GB right now but want the option to upgrade later on, in case the iMac is going to be touchy with slightly different modules. Thoughts?
A bit annoyed as I would rather have bought the 4x16GB all at once for a better price if I knew this was going to be the case. But I guess overall I'm relieved that the 2020 model still allows RAM upgrades, otherwise I'd be a lot more out of pocket...

 

[Azrael9]

cinnamongirl96,

With the help of Whiteman007, just installed my Crucial 2 x16 gigs in slots 1 and 3. 32 gigs total.

The Apple Ram sticks are cast aside for now.

Installing the RAM as per 9to5 instructions creamed my Geekbench 5 results to around 5k-ish multi-core.

(I had the 2x4 gigs of Apple RAM in 1 and 2 and the 2 x 16 gigs Crucial in 3 and 4. Clearly I lost dual channel performance. So? I put the 2 x 16 gigs in 1 and 3 and I get this...)

iMac20,2
Geekbench 5 Score

1237
Single-Core Score
9940
Multi-Core Score

Azrael.

 

[Azrael9]

Looks like I'm in the same boat as everyone else. Had a 2019 iMac on order and planned to do the 8GB+32GB upgrade that was so popular for those models - never came into stock and changed my order to the 2020.

I've just put in 2x16GB OWC modules - tried alongside the Apple RAM initially and had the same 2133 result as everyone else - glad I saw this thread today otherwise I'd be wondering what I'd done wrong! Removed Apple RAM and now running happily at 2667. Found the springs in the RAM door to be pretty touchy, I was very careful to apply even pressure and still managed to bust a couple of them (never done a memory upgrade before so not sure if this is usual) - it's sitting nicely now though. I didn't bother to swap the order of the sticks as I figured my results would be the same as everyone above - I'd rather just have 32GB running optimally right now.

I'm now wondering whether I should order another set of the OWCs straight away. I don't need 64GB right now but want the option to upgrade later on, in case the iMac is going to be touchy with slightly different modules. Thoughts?
A bit annoyed as I would rather have bought the 4x16GB all at once for a better price if I knew this was going to be the case. But I guess overall I'm relieved that the 2020 model still allows RAM upgrades, otherwise I'd be a lot more out of pocket...

...and yes. The Apple ram door is very touchy. Not something I'd want to do a lot of.

I think the 32 gigs is more than enough for now.

Can add 32 gigs later if I need to.

But 3d renders. It cranks Cinebench just fine. Geekbench 5 is a lot higher.

Azrael.

 

[DCIFRTHS]

Interesting. Thanks for sharing this. I wouldn't have though that it would be THAT particular about about RAM. I received my second pair of Crucial RAM yesterday and tried it with the original Apple RAM. I got the same result as the first batch of Crucial I tried with Apple RAM. I'm now using four sticks of Crucial for 32GB at 2667. I did configure it though so that the first pair that I received is in DIMM 0 and the second in DIMM 2. This restored dual channel (vs. Crucial in channel A and Apple in B) and the performance is now as expected.

As an aside, did you order directly from Crucial? If so, did the sticks come in any type of “hard” plastic clamshell, or were they just in anti-static bags? Did the Order ship in a box or envelope? I’m curious because years ago they packed them well, and then went to just anti-static bags in an envelope.

 

[MMidnight]

HI all, just in case someone is interested on some more testing.
I'm using an iMac 27" 2020 i7 3.8Ghz 8 core.
Memory tests and geekbench results:

1. Total amount of RAM: 8Gb
   Stock 8 Gb (2x4) on slots 2 & 4
   Mem. speed: 2667Mhz
   Geekbench results: 1216/7373
   
   
2. Total amount of RAM : 72Gb
   Stock 8 Gb (2x4) on slots 2 & 4 + 64Gb (2x32) Timetec Hynix on slots 1 & 3
   Mem. speed: 2133 Mhz
   Geekbench results: 1217/8180
   
   
3. Total amount of RAM: 72 Gb
   Stock 8Gb (2x4) on slots 3 & 4 + 64Gb (2x32) Timetec Hynix on slots 1 & 2
   Mem. speed: 2667 Mhz
   Geekbench results : 1206/7072
   
   
4. Total amount of RAM : 64Gb
   64Gb (2x32) Timetec Hynix on slots 1 & 3
   Mem. Speed: 2667 Mhz
   Geekbench results: 1203/8612
   
   
5. Total amount of RAM: 64Gb
   64Gb (2x32) Timetec Hynix on slots 2 & 4
   Mem. Speed: 2667
   Geekbench results: 1245/8611

If i can recall properly, Timetec's memory is supposed to be the same as Apple's in terms of timings and CL and featuring Hynix chips (as Apple's does).
To me it has to do with different dimm sizes and addressing memory...it would be interesting if it happens the same mixing 16Gb modules and 32Gb modules as it's a turn down not being able to use those 8Gbs and having them looking at you from the table.

Just in case someone wants to know, while running Geekbench i didn't stop any service (Timemachine, iStats, MacFans Control or any other) and in some of the tests Intel Power Gadget was running at the same time to check for consistency on some data.