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What Ram to order with the new 2019 IMac?
- Thread starter Potts17
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I ordered: 64.0GB (4x 16GB) PC4-21300 DDR4 2666MHz SO-DIMM 260 Pin Memory Upgrade Kit for 2019 iMac models which utilize PC4-21300 SO-DIMM from macsales.com You can also order 32GB in either 2x16GB or 4x8GB.
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I ordered this: https://smile.amazon.com/Crucial-16GBx2-PC4-21300-SODIMM-260-Pin/dp/B071H38422
It’s $30 cheaper than MacSales and seems to be the correct speed and pin layout. Furthermore people seem to have had no problem installing it into the new Mac Mini and I’ve had good luck with Crucial in the past. Make sure you keep your 8GB because there are four slots. Then you can have matched channel pairings to get full speed at 40GB, which is what I’m doing.
Remember too, the iMac 27" has 4 SO-DIMM slots so you can keep the two matched pairs of 4GB Ram (8GB) and add 32GB for a total of 40GB. I'll go 64GB if and when I actually need that much RAM. Have 32GB on my MacBook Pro and sometimes start to touch the ceiling but it happens so infrequently that I think 32GB is more than most people will ever functionally need except for VR/Science Modeling or massive video projects.
32GB for $199 + 8GB included is 40GB and is a ton (as of this writing in 2019, don't quote me in 10 years on my statement).
32GB for $199 + 8GB included is 40GB and is a ton (as of this writing in 2019, don't quote me in 10 years on my statement).
Buy the new iMac with 8gb of RAM (for now).
Sit back 4-6 weeks until "RAM issues" become known (if they are to become known).
THEN consider buying more RAM...
Sit back 4-6 weeks until "RAM issues" become known (if they are to become known).
THEN consider buying more RAM...
I'd wait for the reviews/issues to become public, then order the lowest amount of RAM and buy the additional RAM from Crucial at half the price Apple will charge for essentially the same RAM.
The RAM I linked to above from Crucial doesn't seem to have any issues with the 2018 Mac Mini that uses the same 2666MHz speed and even works in older 2017 iMacs that came with 2400MHz. I'd be pretty shocked if I have any issues with what I purchased. You guys can use me as a guinea pig if you want, but I can always send it back if it has problems and it's only $199. I don't think I could get by for very long on 8GB, lol.
Also, it looks like someone asked them and the manufacturer responded on Amazon:
Crucial is an excellent choice. It is, after all, the consumer division of Micron, Apple's primary vendor. I've seen far fewer reports of issues with Crucial than OWC over the years in these forums.
There won't be issues with the RAM, that wasn't what I was referring to when I said 'issues'. I was referring to the iMac. so far an 8-core CPU in that iMac case is untested - it could thermal throttle a lot, or it could be okay. Wait for the reviews before ordering
Planning purchase of 32 gb RAM, 2 x 16gb, from OWC. Would use the two stock 4gb modules as well for total 40gb RAM. My question is which slots to use for each of these? I guess these need to be paired in some way. In which slots should the larger modules be placed?
If you add two 16GB sticks in the two empty slots to an 8GB iMac, you'll have 40GB. They are 4 slots, two matched pairs so
Two 4GB Sticks
Two 16 GB Sticks
=40
Hi guys! Need your help. I just ordered a BTO iMac 27" and I want to buy another 32gb ram for it.
The problem is I do now know which is compatible and which is not. Its my first time having a mac and upgrading a ram.
I checked the internet and found these:
OWC 32GB Ram ~ 230 USD
https://eshop.macsales.com/item/OWC/2666DDR4S32P/
Crucial 32GB DDR4 2400 MHz SO-DIMM Memory Module Kit ~ 199 USD
https://www.bhphotovideo.com/c/product/1346254-REG/crucial_ct2k16g4s24am_32gb_kit_16gb_x2.html
G.Skill SODIMM 32GB ~ 230 USD
I honestly do not know which is the better option among those 3 so please help me. And if you can suggest a different one, please do so.
Appreciate all the help! Thank you!
The problem is I do now know which is compatible and which is not. Its my first time having a mac and upgrading a ram.
I checked the internet and found these:
OWC 32GB Ram ~ 230 USD
https://eshop.macsales.com/item/OWC/2666DDR4S32P/
Crucial 32GB DDR4 2400 MHz SO-DIMM Memory Module Kit ~ 199 USD
https://www.bhphotovideo.com/c/product/1346254-REG/crucial_ct2k16g4s24am_32gb_kit_16gb_x2.html
G.Skill SODIMM 32GB ~ 230 USD
I honestly do not know which is the better option among those 3 so please help me. And if you can suggest a different one, please do so.
Appreciate all the help! Thank you!
You need The DDR4 2666 MT/s (PC4-21300) DR x8 Sodimm 260 - Pin Memory. Looks like the most inexpensive place is Amazon. https://www.amazon.com/Crucial-16GBx2-PC4-21300-SODIMM-260-Pin/dp/B071H38422?pldnSite=1
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Put the larger RAM modules where the stock ones were.
So long as the matching DIMMs are installed in alternating slots (dual channel) it makes no difference which set goes where in terms of performance.
I added 32GB (2x16GB) to my 2017 iMac and benchmarked it with no difference aside from a marked decrease when the matching DIMMs were not in proper dual-channel configuration.
You can just put the new modules into the empty slots.
Since I was going by a PC motherboard manual, by all means put the new ones in the empty slots if there are no difference with a iMac logic board.
On the base 27 in iMac, it says the maximum RAM is 32 Gb.
I was initially thinking of keeping the 2 x 4 Gb that comes with it and adding another 2 x 16 Gb for 40 Gb in total later like some of you have done here. I presume that isn't possible.
So I presume if I wish to keep the original RAM, the best that I can do is add another 2 x 8 Gb for a maximum of 24 Gb? is this correct?
Thanks
I was initially thinking of keeping the 2 x 4 Gb that comes with it and adding another 2 x 16 Gb for 40 Gb in total later like some of you have done here. I presume that isn't possible.
So I presume if I wish to keep the original RAM, the best that I can do is add another 2 x 8 Gb for a maximum of 24 Gb? is this correct?
Thanks
The "limit" is simply because Apple doesn't want to provision base model machines with maximum memory. This would be an SKU that sells very little. The base model is also not available with an i9 CPU nor the biggest Fusion drive.
Go right ahead and upgrade to 40GB.
Anything wrong with this RAM? https://www.amazon.com/dp/B06XRBS4Y5/ref=psdc_172500_t1_B071H38422
Seems to be very similar to the Crucial RAM that people keep referencing, but potentially faster (CL16 vs CL19) and cheaper.
Seems to be very similar to the Crucial RAM that people keep referencing, but potentially faster (CL16 vs CL19) and cheaper.
I bought this one. And to all, Apple just updated their RAM page for 2019 iMac and it says PC4 21333 and all the RAMs on Amazon are 21300. Does anyone know if it would be compatible?
https://support.apple.com/en-us/HT201191#27inch2019
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Can I use the ram 2400 from the previous imac and mix it with the 2666 in the new 2019 imac? I heard you can but the 2666 is going to get downclock to 2400.
Off on a Hong Kong forum, some guy's iMac already arrived.
The stock RAMs are 4+4GB sticks of SK hynix HMA851S6CJR6N-VK
PC4-21300 2666MHz 1.2V 0.75ns CL19
The stock RAMs are 4+4GB sticks of SK hynix HMA851S6CJR6N-VK
PC4-21300 2666MHz 1.2V 0.75ns CL19