What RAM to buy to update new iMac launched today?

[Packers1958]

Got my RAM today and tried to follow the instructions on the Apple site.

"Replace or install a DIMM by setting it down into the slot and pressing firmly until you feel the DIMM click into the slot. The DIMM slot shown below is for iMac (27-inch, Late 2013) and iMac (Retina 5K, 27-inch, Late 2014, Mid 2015, Late 2015, and 2017). It requires that you insert the DIMM with the notch on the bottom, oriented towards the right:"

The notch is not towards the right on the 2017 model. I tried installing, but it would not click in. Once I oriented the DIMM where the notch was on the left, it snapped right in.

 

[Lando555]

Sorry, but can anyone confirm this RAM will work on both the entry and mid-range new 2017 i5 iMacs Thanks.
https://www.amazon.co.uk/dp/B019FRCV9G/ref=psdc_430511031_t3_B019MRBKYG?th=1

Actually, a lot of users in this thread got this RAM and obviously it works fine (on the 27 inch iMac). I have exactly this 2x16 GB Crucial kit but haven't set up my iMac yet.

 

[cal6n]

This is great! Makes me think that it's maybe a wise move to get 1x16 GB additional RAM instead of 2x8 for a total of 24 GB as that will make the upgrade path easier.

I don't think that'll work in dual channel. You'll have 8GB in channel 1 and 16GB in channel 2. It'll drop into single channel mode.

 

[user1234]

I don't think that'll work in dual channel. You'll have 8GB in channel 1 and 16GB in channel 2. It'll drop into single channel mode.

I didn't think about that. Oh well

 

[MacScott]

I got my new iMac yesterday and ordered another 16g from MacSales.com.

 

[scottw75]

As far as I can tell, the best RAM deal in Europe at this time is a 64 GB kit (4x16) from Corsair Vengeance for 386€ at Amazon France.

https://www.amazon.fr/gp/product/B01BMQAIOI/ref=ox_sc_sfl_title_3?ie=UTF8&psc=1&smid=A1X6FK5RDHNB96

I bought this kit and I can confirm that it works fine on my base model 2017 iMac 27".

The price fluctuates quite a bit on the various european Amazon sites (I actually bought mine even cheaper on the german store, a few days ago), so do look at all the stores (.de, .fr, .it, .es and .co.uk) to find the best deal.

For less than 400€ I think it might be worth it to go for this 64 GB kit rather than spend almost the same amount of money on 32 GB kits from other manufacturers (or even from Corsair themselves).

Presumably this will be ok with the i7 4.2ghz imac?

I'd budgeted £270 for 32gb and the 64gb kit is £389 at the moment on amazon uk. Tempted just to max it out and be done with it.

 

[Soepie]

Actually, a lot of users in this thread got this RAM and obviously it works fine (on the 27 inch iMac). I have exactly this 2x16 GB Crucial kit but haven't set up my iMac yet.

Same here, 2 27" i5 iMacs running with the same memory and working just fine.

 

[Brazilano]

My i7/580, 1tb SSD, is coming this week. I've just bought "used" 8gb from another new iMac on eBay. 31 bucks with free shipping!!!

For whom that don't need more than 16gb, I think it's the best option.

 

[eonaeon]

I just noticed that RAM prices have steadily rose since mid last year - they haven't dropped down again. Anyone intending to see how their machine runs with 8GB and upgrade later when the RAM prices come down again (if they do?)

Edit: ok reading the article on Toms Hardware (http://www.tomshardware.com/news/ssd-hdd-shortage-nand-market,33112.html) Looks like the high prices are here to stay probably into 2018... May as well just buy the RAM now then!

 

[geoelectric]

TBH, I've gone as far as I'm going with this. I've always understood that multi-channel works with equal quantities of similarly specced RAM in each channel. The easy way to achieve this in a dual channel machine is to install paired DIMMS across the channels, but it's not the only way.

I'm satisfied that I've got 16GB installed cheaply and working efficiently in dual-channel mode. If I need any more RAM in the future, I'll add another stick of the same Crucial RAM, rearranging it to 4-8-4-8.

Thanks so much for the followup. This has been fascinating, and I'm very impressed with the detail and diligence.

 

[randian]

Anyone intending to see how their machine runs with 8GB and upgrade later when the RAM prices come down again (if they do?)

That's my plan. I might get some cheap 8GB sticks from somebody selling their originals and run with 16GB though.

 

[Arctic Moose]

Just got my second Crucial CT2K16G4SFD824A kit.

Here's the geekbench results with one Crucial kit and the stock RAM (40 GB) showing memory scores of 5519/5946:
https://browser.geekbench.com/v4/cpu/3314462

And here's the results with two Crucial kits (4x16 = 64 GB) showing memory scores of 5603/6095:
https://browser.geekbench.com/v4/cpu/3314528

Latency actually increased from 72.6/72.9 ns to 73.7/74.0 ns. The lowest latency I've seen is still a configuration with only the 8 GB stock RAM mounted.

 

[EugW]

Just got my second Crucial CT2K16G4SFD824A kit.

Here's the geekbench results with one Crucial kit and the stock RAM (40 GB) showing memory scores of 5519/5946:
https://browser.geekbench.com/v4/cpu/3314462

And here's the results with two Crucial kits (4x16 = 64 GB) showing memory scores of 5603/6095:
https://browser.geekbench.com/v4/cpu/3314528

Latency actually increased from 72.6/72.9 ns to 73.7/74.0 ns. The lowest latency I've seen is still a configuration with only the 8 GB stock RAM mounted.

The score differences you show are within the margin of error of Geekbench. IOW, those scores are effectively identical, unless you've run them 25 times each or whatever.

 

[shaunp]

Can we please have this as a sticky - look at the Crucial/OWC website....

 

[Arctic Moose]

The score differences you show are within the margin of error of Geekbench. IOW, those scores are effectively identical, unless you've run them 25 times each or whatever.

Yeah, not concerned about it, should have pointed out that if anything I was surprised I didn't see a greater difference. It is nice to see the multi-core score over 20000 though.

 

[iska]

I'm about order some RAM for my 2017 27" iMac. I'd be fine with 8 GB. Should I go with 2x4 GB is or 1x 8GB fine? Is dual or single rank important?

 

[userjohn]

Additional to the Kingston hyperx cl14 I have 64GB crucial ballistix here with cl16 that I be able to test. And on Saturday will arrive crucial ballistix 2*32GB kit ddr4-2666, that I also will test.

Have you or anyone here yet tested the Crucial Ballistix 2666MHz to see how it compares to the Kingston HyperX 2400MHz CL14?

For the maximum possible performance (which presumably would require replacing the stock RAM), which product appears to be the best option for now (not necessarily limited to the two choices above)?

 

[Arctic Moose]

I'm about order some RAM for my 2017 27" iMac. I'd be fine with 8 GB. Should I go with 2x4 GB is or 1x 8GB fine? Is dual or single rank important?

If you only want 8 GB, for a 16 GB total, your best bet is buying stock RAM that someone else has taken out to put more in. It will definitely be cheaper, all four of your RAM modules will be identical and it'll be good for the environment.

 

[Azenha]

Presumably this will be ok with the i7 4.2ghz imac?

I'd budgeted £270 for 32gb and the 64gb kit is £389 at the moment on amazon uk. Tempted just to max it out and be done with it.

It works fine with my i5 3.4ghz base iMac so it'll most certainly work just as well with the i7.

 

[meady100]

I've just tried installing a 16GB kit into my i7 2017 Mac, and I get a black screen. Some power is coming in, as I can feel a faint draught from the rear fan vent. Could anyone more knowledgeable confirm that I have bought the right spec here, please? I installed it in the remaining empty sockets. Definitely pushed it in firmly enough as I can uninstall and reinstall the original dimms no problem:

https://www.overclockers.co.uk/?sViewport=detail&sArticle=60425

 

[kblbn86]

I've just tried installing a 16GB kit into my i7 2017 Mac, and I get a black screen. Some power is coming in, as I can feel a faint draught from the rear fan vent. Could anyone more knowledgeable confirm that I have bought the right spec here, please? I installed it in the remaining empty sockets. Definitely pushed it in firmly enough as I can uninstall and reinstall the original dimms no problem:

https://www.overclockers.co.uk/?sViewport=detail&sArticle=60425

Kingston HyperX have some compatibility issues with Apple stock ram.

Even if you can get it to work it will downclock to 2133 Mhz.

Try;

- installing Kingston Rams one at a time.

- removing stock rams and installing Kingston Rams only one at a time

- installing to different DIMM slots 1-3 and 2-4 while trying above

see if those help.

 

[meady100]

Kingston HyperX have some compatibility issues with Apple stock ram.

Even if you can get it to work it will downclock to 2133 Mhz.

Try;

- installing Kingston Rams one at a time.

- removing stock rams and installing Kingston Rams only one at a time

- installing to different DIMM slots 1-3 and 2-4 while trying above

see if those help.

Yes!!! I owe you a beer. Shifting my stock ram from slots 2 & 4 to slots 3 & 4, then installing my new ram in slots 1 & 2 (I was previously using slots 1 & 3) has solved the problem. It is all now showing on my OS. Don't know what speed though, I assume you need an app? I'm happy, anyway!

You trumped the Applecare. My first call, they insisted I took the machine in, without asking me to try swapping the dimms around or asking what type of ram it was, even, and the second call to an Applecare franchisee told me I shouldn't be using third party ram!

Thanks again! Let me know if there is an easy way to check speeds?

 

[SaSaSushi]

Yes!!! I owe you a beer. Shifting my stock ram from slots 2 & 4 to slots 3 & 4, then installing my new ram in slots 1 & 2 (I was previously using slots 1 & 3) has solved the problem. It is all now showing on my OS. Don't know what speed though, I assume you need an app? I'm happy, anyway!

Click the Apple at the top left of the Menu Bar > About This Mac > Memory

 

[kblbn86]

Yes!!! I owe you a beer. Shifting my stock ram from slots 2 & 4 to slots 3 & 4, then installing my new ram in slots 1 & 2 (I was previously using slots 1 & 3) has solved the problem. It is all now showing on my OS. Don't know what speed though, I assume you need an app? I'm happy, anyway!

You trumped the Applecare. My first call, they insisted I took the machine in, without asking me to try swapping the dimms around or asking what type of ram it was, even, and the second call to an Applecare franchisee told me I shouldn't be using third party ram!

Thanks again! Let me know if there is an easy way to check speeds?

You're welcome. Good to hear you got it working

 

[Bob418]

I cancelled the Crucial (iMac model) 32GB order as the waiting time is too long. I now ordered Corsair Vengeance 32GB package. It is $15 cheaper and all the reports for it are positive. Amazon Global shipping still need about 2 weeks time to deliver.