Late 2015 27 iMac 5k RAM spec

>> ]Its funny cause your asking for 3rd party ram when all apple sells is 3rd party ram. <<

I think it's more a case of people not wanting to buy from Apple directly cuz of their grossly overpriced rates on Ram. Hence "first party".

I was always under the impression that the two banks should match if running dual-channel when all 4 banks are filled. But, if running dual channel with only 2 dimms, then they should be installed with 1 dimm in Bank 0 and 1 dimm in Bank. This is it how it has worked with all of my Intel motherboards so far as I used to mostly use PC? If I am wrong, please correct me because I'm trying to figure this out with no available info from apple on the late 2015 iMACs.

I've asked around and it appears the way I have it set up is the correct way. The computer came from the factory with the original ram staggered.

Hi everyone, i'm writing from Italy asking your help, sorry if my english is not perfect. I'm planning to buy new Imac 275k and want to upgrade ram to 32gb. Can you say me if this will fit correctly?http://www.amazon.it/gp/product/B00VMCUBK4?psc=1&redirect=true&ref_=ox_sc_act_ti tle_2&smid=A11IL2PNWYJU7H I think this is the right choice but i'd like you confirm me. Thank you very much

Not sure to be honest, but this is the correct memory for the computer. This company is very reliable. I bought my memory from them.

http://eshop.macsales.com/item/Other%20World%20Computing/1867DDR3S32S/

Thanks i've already seen that one you linked but you have to know that i risk to pay extra taxes if i buy from States to Italy :-(

I pretty sure someone in this session has the answer. Best of luck with you're search. Keep us posted.

Maybe this one from Crucial could be right too http://www.amazon.it/gp/product/B00LTV2BBK?keywords=ram%20pc3%2014900&qid=144675 7736&ref_=sr_1_4&sr=8-4

Melquiades38 ,

That RAM looks good to me.

The three things to look for are
- DDR3 - kind of memory
- PC-1866 - speed
- SO-DIMM - form factor (size/shape)

If you see those 3 things it will work.

Thank you so much Bringer i totally agree with you: i'm going to buy it.

Has anyone found a 32gb (2x16gb) kit that works for this iMac, other than the OWC option?

Yes I did, SillyGuy.

My iMac is a Late 2015 27" Retina Display. Bought 32Gb of Ram from Crucial, and installed it. Replaced the 8Gb that was in there (and keeping it, in case I run into a problem). Anyway, this is what I got:

http://www.crucial.com/usa/en/ct2kit102464bf186d

Amazon is selling this too, but they're having an issue keeping it in stock, which tells me others are buying it too. 🙂

http://www.amazon.com/gp/product/B00JCRZ6XS/ref=as_li_tl?ie=UTF8&camp=1789&creat ive=390957&creativeASIN=B00JCRZ6XS&linkC…

@Bringer42, have you tried installing your Crucial RAM alongside the existing Apple RAM? I have not yet received my new iMac but already bought 2x8GB of the same Crucial RAM. I was hoping to upgrade from the stock 8GB to 24GB.

No. I completely replaced the original ram with 2 pairs of 8Gb modules.

But what you describe should work fine. Just be sure to alternate the modules (e.g. Apple-Crucial-Apple-Crucial). That will happen automatically if you leave the Apple memory in the slots it comes in.

The worst that might happen is that Crusual memory may be slowed down to the speed of the Apple memory. But that difference would be imperceptible.

I contacted Crucial Support and they advise against using Ballistix Sport RAM with the new iMac. I'm not sure what to make of that. Clearly people like yourself are using it successfully. Sounds to me like they want us to wait for something more expensive.