RAM RAM once Again ;-)

pscl

macrumors 6502
Original poster
Jun 3, 2013
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hey

im looking for the best ram to upgrade my late 2013 imac.

i still got the 8GB and want to purchase 16 gb...

wich one is the fastest and will (really) boost my system?


i read a lot of articles about this topic... but i wanted to ask my trusted macrumors friends ;)
 

Weaselboy

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Jan 23, 2005
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The easiest way is to use Crucial's system scanner here to ID the specs for the RAM your system uses. You can then either buy from Crucial or write down the specs from the Crucial scan results and get that same spec RAM from any vendor (Amazon / Newegg or whatever) you trust.

As long as it meets the specs it will work and it will be the same speed.

Unless you are doing some heavy lifting there, you may not benefit at all by going from 8 to 16GB. See this test.
 

Weaselboy

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Weaselboy: That test holds true for Mountain Lion, but not for Mavericks as it utilizes all available RAM to cache files and speed up the system.
I understand your point, but if OP has eight now and that is not even being fully utilized, 16GB will make zero difference.

Here is me with 8GB on Mavs. 16GB would do nothing for me with my usage pattern.

 

pscl

macrumors 6502
Original poster
Jun 3, 2013
393
61
im using parallels so i need a little bit more ram than the stock 8GB i have,

but for me its also about the speed. i dont know if i will feel a difference in loading games, programs e.g. with the corsair vengeance... ?

will there be a (little) speed boost or is it completely unnecessary to buy faster ram?
 

Weaselboy

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Jan 23, 2005
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im using parallels so i need a little bit more ram than the stock 8GB i have,

but for me its also about the speed. i dont know if i will feel a difference in loading games, programs e.g. with the corsair vengeance... ?

will there be a (little) speed boost or is it completely unnecessary to buy faster ram?
Ah... Parallels VM is a hog. :)

Here (for $148) is the standard Crucial RAM called for for your iMac.

You iMac uses the Intel Core i7 4770S chip here, and that chip will not run memory at 1866MHz. If you install 1866Mhz memory, it should (?) work but it will be underclocked to the 1600MHz the chip supports and provide no benefit over the stock 1600MHz memory.
 

pscl

macrumors 6502
Original poster
Jun 3, 2013
393
61
Ah... Parallels VM is a hog. :)

Here (for $148) is the standard Crucial RAM called for for your iMac.

You iMac uses the Intel Core i7 4770S chip here, and that chip will not run memory at 1866MHz. If you install 1866Mhz memory, it should (?) work but it will be underclocked to the 1600MHz the chip supports and provide no benefit over the stock 1600MHz memory.
thank you!
 

SaSaSushi

macrumors 601
Aug 8, 2007
4,084
479
Takamatsu, Japan
Here (for $148) is the standard Crucial RAM called for for your iMac.
I am using 16GB of this very RAM purchased from Amazon US in combination with 16GB of stock Apple Elpida and it is running perfectly.

The Haswell iMacs are notoriously sensitive with upgrade RAM, particularly in 32GB configurations. See this thread for more information.

You iMac uses the Intel Core i7 4770S chip here, and that chip will not run memory at 1866MHz.
Unless he has the CTO Core i7-4771 (3.5GHz) :p but it's the same deal.
 

Weaselboy

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If you go by Intel's ARK, people with 3000MHz memory would have them in a picture frame above their desks instead of installed in their computers.

Here's an iMac with the i7-4771 CPU, running 1866MHz RAM for example (from this thread).
I don't understand what you are trying to show with these links? Like I said, that Intel chip will not run RAM at 1866MHz and I don't see anything you linked showing otherwise. If you have some evidence of a 2013 iMac running RAM at 1866MHz that results in a performance increase, can you please explain it, because I'm not seeing it.
 

SaSaSushi

macrumors 601
Aug 8, 2007
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Takamatsu, Japan
Here's an iMac with the i7-4771 CPU, running 1866MHz RAM for example (from this thread).
As mentioned above, you'll have enough trouble finding third party RAM that runs stably in the Haswell iMacs at 1600MHz, particularly at 32GB.

You may want to have a look-see at this thread (highlighted for your pleasure) and this post in particular regarding the higher speed Ripjaws RAM.

That is not mention that my own Geekbench scores at 1600MHz are nearly identical to the 1866MHz ones you linked to.

----------

If you have some evidence of a 2013 iMac running RAM at 1866MHz that results in a performance increase, can you please explain it, because I'm not seeing it.
Excellent point. As mentioned, I am seeing nearly identical Geekbench scores @1600MHz.
 

Giuly

macrumors 68040
If you have some evidence of a 2013 iMac running RAM at 1866MHz that results in a performance increase, can you please explain it, because I'm not seeing it.
To be fair, Crucial's forums are also plastered with reports of crashing 2013 iMacs with the standard RAM.

This is 16GB 1600MHz, likely stock CL11.


This is 32GB 1600MHz, likely CL9.


And this is 1866MHz CL10.


Technically, he asked for the fastest. Theoretically (and synthetically), it is. Practically, Ripjaws != Crucial Ballistix, Corsair Vengeance and Kingston HyperX Plug'n'Play, but nobody could tell a difference between 1866MHz CL10 and 1600MHz CL9 anyways.

Kingston HyperX Plug'n'Play at 1600MHz and 1.35V should, according to the limited reports, run fine for 2013 iMacs, even alongside stock RAM, if you're unwilling to see whether the 1866MHz version at the same price (which also has been reported to work fine, supposedly because it's not CL10 like the others but CL11) and replace it if it doesn't work for your particular Mac.
 
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SaSaSushi

macrumors 601
Aug 8, 2007
4,084
479
Takamatsu, Japan
Technically, he asked for the fastest. Theoretically (and synthetically), it is. Practically, Ripjaws != Crucial Ballistix, Corsair Vengeance and Kingston HyperX Plug'n'Play, but nobody could tell a difference between 1866MHz CL10 and 1600MHz CL9 anyways.
Assuming 1866MHz RAM actually runs at those speeds in the iMac, we seem to be talking about a meager boost (10-15%) in benchmark results. Exactly how does that translate into noticeably improved performance in actual usage? Is it worth the higher price tag to find 1866MHz modules that work?

It's hard enough to find RAM at Apple's own specs that runs stably.

If you go by Intel's ARK, people with 3000MHz memory would have them in a picture frame above their desks instead of installed in their computers.
I think the folks going to the trouble of getting 1866MHz to run on their Haswell iMacs should probably have their Geekbench results in a picture frame above their desks.

There has to be some reward.