To those of you who opted to get the Late 2015 5k iMac with 8gb and decided to upgrade the RAM themselves. Which RAM sticks did you buy and from where?
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Which RAM for Late 2015 5k iMac?
- Thread starter jinyoungkim7
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Kingston Technology HyperX Impact Black 8GB 2133MHz DDR3L 1.35V Laptop Memory (HX321LS11IB2/8)
Bought from Amazon, was only a few dollars more than the type that came with the computer. I have had no issues, and have just liked having the extra memory occasionally.
Bought from Amazon, was only a few dollars more than the type that came with the computer. I have had no issues, and have just liked having the extra memory occasionally.
'Corsair Vengeance Performance 16GB (2x8GB) DDR3 1866MHz Laptop Memory' via Amazon (it was $89 a pair when I bought it).
http://www.amazon.com/gp/product/B00FMRV7R6?psc=1&redirect=true&ref_=oh_aui_detailpage_o07_s01
http://www.amazon.com/gp/product/B00FMRV7R6?psc=1&redirect=true&ref_=oh_aui_detailpage_o07_s01
Could I steal this thread for a moment regarding RAM for iMacs. I've been searching the internet but I can't really find anything definitive. I'm trying to figure out if it matters which banks/DIMM you put the RAM in in order for it to run dual channel.
Some say you should run your identical twin RAM modules in the same BANK others same DIMM pair.
I upgraded my iMac from 8GB(2x4) to 16GB (2x8) and when I opened the backside the factory sent 2x4GB RAM were placed in slot 2 and 4 and when looking at "about this mac" and "memory", they are top next to each other. And when looking in the sys. info, it says:
BANK0/DIMM0 4GB
BANK1/DIMM0 4GB
BANK0/DIMM1 empty
BANK1/DIMM1 empty
So what I get from this is that the "DIMM0" is paired and not the "BANKS", I don't know...
I simply don't get it really, does it all matter, dual channel or not, pairing or not? Can't find anything about it from Apple themselves...
some help please
Some say you should run your identical twin RAM modules in the same BANK others same DIMM pair.
I upgraded my iMac from 8GB(2x4) to 16GB (2x8) and when I opened the backside the factory sent 2x4GB RAM were placed in slot 2 and 4 and when looking at "about this mac" and "memory", they are top next to each other. And when looking in the sys. info, it says:
BANK0/DIMM0 4GB
BANK1/DIMM0 4GB
BANK0/DIMM1 empty
BANK1/DIMM1 empty
So what I get from this is that the "DIMM0" is paired and not the "BANKS", I don't know...
I simply don't get it really, does it all matter, dual channel or not, pairing or not? Can't find anything about it from Apple themselves...
some help please
+1 I bought my 27 inch late 2015 (3.3 GHz i5, 2TB Fusion) with 8GB RAM and installed an additional 16GB of OWC RAM. No problems at all, runs great!
Here is my setupCould I steal this thread for a moment regarding RAM for iMacs. I've been searching the internet but I can't really find anything definitive. I'm trying to figure out if it matters which banks/DIMM you put the RAM in in order for it to run dual channel.
Some say you should run your identical twin RAM modules in the same BANK others same DIMM pair.
I upgraded my iMac from 8GB(2x4) to 16GB (2x8) and when I opened the backside the factory sent 2x4GB RAM were placed in slot 2 and 4 and when looking at "about this mac" and "memory", they are top next to each other. And when looking in the sys. info, it says:
BANK0/DIMM0 4GB
BANK1/DIMM0 4GB
BANK0/DIMM1 empty
BANK1/DIMM1 empty
So what I get from this is that the "DIMM0" is paired and not the "BANKS", I don't know...
I simply don't get it really, does it all matter, dual channel or not, pairing or not? Can't find anything about it from Apple themselves...
some help please
I was using Corsair Vengeance Ram. Was using 32GB and the iMac accepted the ram at 2133mhz. I would not suggest getting it to mix and match with different ram. The ram worked well for me and have been using corsair for years with my macs. http://www.newegg.com/Product/Produ...nce_sodimm_204_2133mhz-_-20-233-889-_-Product
I just received my 32GB of 2133 Kingston HyperX tonight. So I'll be putting it through it's paces of the next week or two to see how the system does.
In my 2013 I have 32GB of Crucial Ballistix and 1 stick ended up going bad a little over a year. I contacted Crucial and they told me to send it back and I received the replacement stick last week with a little over a week turn around from shipping to receiving.
In my 2013 I have 32GB of Crucial Ballistix and 1 stick ended up going bad a little over a year. I contacted Crucial and they told me to send it back and I received the replacement stick last week with a little over a week turn around from shipping to receiving.
Could I steal this thread for a moment regarding RAM for iMacs. I've been searching the internet but I can't really find anything definitive. I'm trying to figure out if it matters which banks/DIMM you put the RAM in in order for it to run dual channel.
Some say you should run your identical twin RAM modules in the same BANK others same DIMM pair.
I upgraded my iMac from 8GB(2x4) to 16GB (2x8) and when I opened the backside the factory sent 2x4GB RAM were placed in slot 2 and 4 and when looking at "about this mac" and "memory", they are top next to each other. And when looking in the sys. info, it says:
BANK0/DIMM0 4GB
BANK1/DIMM0 4GB
BANK0/DIMM1 empty
BANK1/DIMM1 empty
So what I get from this is that the "DIMM0" is paired and not the "BANKS", I don't know...
I simply don't get it really, does it all matter, dual channel or not, pairing or not? Can't find anything about it from Apple themselves...
some help please
I think you're right, it's the DIMM0/1 slots that must be paired, not the banks. Mine came with the stock 8GB placed like yours. I just upgraded to my 2x8GB Kingston HyperX 2133 and placed them in the same Bank (lower 2 slots...ended up being BANK1). I ran Geekbench and was surprised to see lower scores than with the stock RAM, pulled down by the memory scores (which across the board were 1000 points, or ~33%, lower than initially). I suspect I'm not getting dual channel and will reinsert in the same configuration as factory (i.e. slots 1 and 3 or 2 and 4).
EDIT: Confirmed, the dual-channel is between DIMM#, not Bank#. Swapped my RAM around and got the expected boost in Geekbench above my factory specs. FYI, from top to bottom as you look at the physical compartment, the RAM slots are:
BANK0/DIMM1 [top]
BANK0/DIMM0
BANK1/DIMM1
BANK1/DIMM0 [bottom]
Not what I would have expected, but there it is.
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