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Memory upgrade compatibility list for iMac 2019-2020
- Thread starter pldelisle
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Wondering if I can get thoughts on a 128gb kit. I guess only OWC has one listed in the first post. What do you think of OWC memory?
The Crucial stuff is confusing. Could I just order two 64gb kits? (2 x CT2K32G4S266M)? There's also CT2K32G4SFD8266 but still not clear what the difference is there between those two. CT2K32G4S266M is out of stock in Amazon. I prefer Amazon due to easy return if it doesn't work.
The Crucial stuff is confusing. Could I just order two 64gb kits? (2 x CT2K32G4S266M)? There's also CT2K32G4SFD8266 but still not clear what the difference is there between those two. CT2K32G4S266M is out of stock in Amazon. I prefer Amazon due to easy return if it doesn't work.
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OWC is fine.
But Crucial is number one for me. Order it directly on Crucial if Amazon is out of stock.
Are these compatible to run in dual channel full speed together with the Apple's stock ram?
ie. if i get 2x16 and then keep the 2x4 from Apple I get 40gb total and no issues, please?
ie. if i get 2x16 and then keep the 2x4 from Apple I get 40gb total and no issues, please?
Many reports that memory falls to 2133 MHz when mixing anything with stock Apple RAM.
I don't think it's possible to mix anything with the stock RAM. Mac is shipped with SK Hynix RAM specifically for it. It's virtually impossible to buy the same RAM aftermarket. So I would sell the stock modules to someone who wants 16 GB in its iMac (this will obviously work because it would have the same stock modules) and get all-Crucial memory kits.
Ok. Thank you.
So I checked on Hynix's website what SODIMM RAM they are offering right now and I got this:
Apparently the letter before "JR6N" shows on what die (whatever that is) memory chip is based on. So HMA851S6DJR6N-VK (which is the model present in the base model iMac 2020 as stated above in this thread) is based on D-die (according to its technical data sheet) and the HMA81GS6CJR8N model I mentioned before is based on C-die (according to its technical data sheet).
Therefore judging by the information provided on Hynix's website - most similar 8GB RAM chip to the RAM which Apple is putting in the iMac is the HMA81GS6DJR8N-VK model.
I will buy two 8GB chips of those and try to run 24GB of RAM on 2666Mhz. Wish me luck haha
PS. I wonder what memory chips is Apple putting into the iMac 2020 configured with 16GB of RAM. 4x 4GB? 2x8GB? What model of 8GB?
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Good luck.
100% sure it’s 4x4. Apple can buy higher number of modules from Hynix so it saves more.
I don't see why it shouldn't work. They have the exact same specs... Maybe the chat guy just read his sheet of paper.
Yeah, I'm thinking the same.It makes zero sense to me that it shouldn't work if the specs are identical.
Maybe I will take one for the team and actually try them out...
when you click on "full specs", these were the only differences I noticed:
CT2K32G4S266M:
PC speed - PC4-21300 (peak data transfer rate MB/s)
2048Meg x 64 • lead free • halogen free • for Mac
CT2K32G4SFD8266:
PC speed - PC4-25600 (peak data transfer rate MB/s)
I guess it could be a typo; or maybe they just peak differently, even tho they are both PC4-21300, no idea.
What are your thoughts on this memory for a 2020 27" iMac?
www.hyperxgaming.com
The 2666Mhz is on sale for $194 for 64GB (2x32GB)
HyperX | High Quality Gaming Gear
HyperX is a brand committed to making sure every gamer feels they are included. No matter who you are, or what you play, WE'RE ALL GAMERS.
The 2666Mhz is on sale for $194 for 64GB (2x32GB)
What are your thoughts on this memory for a 2020 27" iMac?
HyperX | High Quality Gaming Gear
HyperX is a brand committed to making sure every gamer feels they are included. No matter who you are, or what you play, WE'RE ALL GAMERS.
The 2666Mhz is on sale for $194 for 64GB (2x32GB)
Not compatible. Please refer to first post for all Kingston certified compatible modules.
According to Kingston Support, it works with the 2017 iMac. Which is why I was asking.
I wouldn't take any chance. Anyway, you don't need HyperX branded RAM. The Kingston ValueRAM is plenty enough.
Normally I would agree. I am not looking to overclock the RAM. But at $194 for 64GB that is a pretty good deal. Cheapest I can kind Valueram is $300 for 64GB. That a $100 difference.
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Well, try it to see if it works. if not, return them and take ValueRAM.
I wouldn't try if it was my money. It's your call.
So looking like this are questionable and probably will not work being dual rank and not on the list?
Crucial 32GB Kit (16GBx2) DDR4 2666 MT/s (PC4-21300) DR x8 SODIMM 260-Pin Memory - CT2K16G4SFD8266 https://www.amazon.com/dp/B071H38422/ref=cm_sw_r_cp_api_i_xefpFb87V1MRF
Crucial 32GB Kit (16GBx2) DDR4 2666 MT/s (PC4-21300) DR x8 SODIMM 260-Pin Memory - CT2K16G4SFD8266 https://www.amazon.com/dp/B071H38422/ref=cm_sw_r_cp_api_i_xefpFb87V1MRF
Can someone help with a working version to add another 8GB to the standard version iMac to bring it to 16GB? Something to keep the dual channel, so 2 x 4GB modules.
I got my 2 sticks of CT32G4SFD8266 today, which the Cruical website said wouldn't work.
I decided to try them out, replaced the 2x4gb with the new sticks. Originally thought I would keep the original 8gb, but due to the experiences from the other tread I decided to leave them out.
Machine booted ok, no problems so far.
Ran the Geekbench cpu & compute tests before/after:
stock 8gb
Single-core 1245
Multi-core 8109
Open-CL 57299
new 64gb
Single-core 1267
Multi-core 9991
Open-Cl 51199
Ran Open-Cl a second time due to the big difference, got 54107...
Open-Cl #3rd 54772
Open-Cl #4th 56199
Thought GeekBench was decent, not sure why it is all over the place in the compute test?
I decided to try them out, replaced the 2x4gb with the new sticks. Originally thought I would keep the original 8gb, but due to the experiences from the other tread I decided to leave them out.
Machine booted ok, no problems so far.
Ran the Geekbench cpu & compute tests before/after:
stock 8gb
Single-core 1245
Multi-core 8109
Open-CL 57299
new 64gb
Single-core 1267
Multi-core 9991
Open-Cl 51199
Ran Open-Cl a second time due to the big difference, got 54107...
Open-Cl #3rd 54772
Open-Cl #4th 56199
Thought GeekBench was decent, not sure why it is all over the place in the compute test?
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