iMac Ram Upgrade - Can I add 1 8GB module?

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Chris
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I have a 2013.5 (late 2013) 27" iMac with 8GB RAM, which has been running slow for a while. There is plenty of space on the hard drive, and the processor doesn't appear to be working anywhere near capacity. However the RAM is constantly running at around 7GB when Lightroom is open. So I have decided to upgrade the RAM to 16GB. Ideally I would like to do this by adding an 8GB card, this way I still have a spare slot and can add another 8GB card at a later date (taking it to 24GB). My question is can I add 1 module on its own or does it need to be in pairs. I don't really want to add any 4gb cards as it will cost more to upgrade further in the long run.

Thanks for your help
 
Firstly, this is only worth doing if your system is paging (Swap) a lot, if it isn't then more memory won't make a difference.

But, an 8GB unit will work and I THINK nowadays it won't result in reduced performance vs 2x4GB so should be fine (it used to be matched pairs were preferable).

But still, unless you are running out of RAM more of it won't speed up the machine.
 
Firstly, this is only worth doing if your system is paging (Swap) a lot, if it isn't then more memory won't make a difference.

But, an 8GB unit will work and I THINK nowadays it won't result in reduced performance vs 2x4GB so should be fine (it used to be matched pairs were preferable).

But still, unless you are running out of RAM more of it won't speed up the machine.

Sorry to be an idiot but what is meant by paging?

I don't think it's running out but it's running very close to the limit.
 
You CAN add just one 8gb stick, but some sources indicate that there could be a performance hit of 10% or more - due to imacs running dual channel memory, ie the memory in the first pair of slots needs to be the same value and type, plus the memory in the second pair of slots needs to be the same value and type, but not necessarily the same value as the first pair - ie 2x8 and 2x4 or 4x4 or 4x8 f'r'instance.

The above is theoretical maximum performance, if you're losing speed due to pageouts, you could improve performance by adding ONE 8gb stick which MAY outweigh the losses due to not using dual channel memory (matched pairs that is)

Clear as mud eh?
 
So, you're using enough swap file to make more RAM a good thing, personally I would get 2x4GB due to the above point and 16GB is more than you will ever need but a single 8GB will work.
 
ie the memory in the first pair of slots needs to be the same value and type, plus the memory in the second pair of slots needs to be the same value and type, but not necessarily the same value as the first pair - ie 2x8 and 2x4 or 4x4 or 4x8 f'r'instance.

Ah yes, that's where it has changed, it used to be that all pairs of slots needed to be the same value but now it is just pairs of slots I believe.
 
So, you're using enough swap file to make more RAM a good thing, personally I would get 2x4GB due to the above point and 16GB is more than you will ever need but a single 8GB will work.

So would there be any benefit in adding 2 x 8gb to give a total of 24GB or is that just overkill. The main use is to edit photos from my A7Rii (40-50mb files)
 
So would there be any benefit in adding 2 x 8gb to give a total of 24GB or is that just overkill. The main use is to edit photos from my A7Rii (40-50mb files)

Overkill really, unless you are editing multiple TIFF files in photoshop.

Adding RAM is a bit like fuel in a car. Putting more in won't make the car any faster but you need enough to get where you need to go. For photo editing 16GB will be plenty, after all your files are only in the MB range, but when converted to 16bit TIFF files they will be more like 1-2GB so if you are opening lots then you want more RAM, for example if they are 2GB each then 4 files will take up 8GB RAM.
 
Have you considered closing programs that aren't in immediate use? That could save you quite a bit of memory & speed things up.
 
Just looking at your memory usage and a few things aren't quite right.

Nearly a gig for Adobe services? mine's at 100mb
Applespell? what's that? Kill it I would
400mb for Amazon music? seems a lot
And then you have DXO open at the same time as LR

More RAM will sort this so knock yourself out but there are a few things there I would be looking sorting at first.

edit: and over 1gb of Adobe Creative Cloud? that's wrong, needs fixing.
 
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I'm curious - when I used a Mac for LR (5.7) it would use about 3.2Gb out of the 4 available, and taking it up to 8Gb made no difference to performance. What did make a difference was what other software I had running in the background, and even simply opening and closing a program would both leave stuff behind in memory and also make the computer slower processing images, even when LR was the only application I had running at the time.
 
Here's my Macbook Pro right now with LR open:

Snip20170908_2.png

8GB is more than enough for daily use and using LR (and PS), you just need to make sure you don't have any resource hogs/leaks running. Occasionally you need to kill a program so it runs smoothly (i.e. when editing TIFFs in PS I will kill Safari) but in day to day use as a photo editing machine 8gb is enough.

Again, not saying don't get more memory but equally don't do so unnecessarily.
 
Just looking at your memory usage and a few things aren't quite right.

Nearly a gig for Adobe services? mine's at 100mb
Applespell? what's that? Kill it I would
400mb for Amazon music? seems a lot
And then you have DXO open at the same time as LR

More RAM will sort this so knock yourself out but there are a few things there I would be looking sorting at first.

edit: and over 1gb of Adobe Creative Cloud? that's wrong, needs fixing.
Thanks for taking the time, as you can probably tell I am not the most technical when it comes to the software side. Ive always thought something seemed wrong with Creative Cloud but didn't know what as all it does is sit at the top of the screen. After googling Applespell which is something to the with OS and spell checking etc.
Also the reason I have both LR and DXO open is because I use LR to review and rate then open in DXO to edit before export the tiff back to LR
 
No Probs :)

It might be worth taking the time to google every line of your activity monitor with "high memory usage" and seeing what turns up. Adobe CC definitely shouldn't be using 1GB.

By all means get the extra RAM as it is useful on occasion but it would be worth trying to sort out these memory hogs irrespective.
 
Creative Cloud has dropped right down now since I re-started. Thinking about it I'm not sure when the last time I turned it off was. Would this make a difference, I know it does with Windows machines, but I thought it didn't matter with Macs?
 
I just upgraded my i7 with 16GB (2x8GB) memory - I already had 4x4GB so added it to the i7 which gave me 16GB +8GB =24GB.

I don'y have all the issues that others seem to since I disabled paging and also run everything in VMs so there's no real (as far as I know) interaction between various processes.

Just makes life so much easier as far as I'm concerned.

And the extra memory means I can now run 16 VMs all rendering away quite happily.
 
Lots of people think that (which is why no-one mentioned it, that or it would be the first thing to try) but the evidence before us suggests otherwise.

Macs suffer just as much, but I thought the OP had said re-starting didn't make any difference.
 
Overall it is still on the slow side (by my standards), but the RAM usage is more in line with yours.

I know it wouldn't cause a ram problem, but it could cause things to run slower, due to the higher demands of new OS and software.


Yes, generally being a bit slow is because it's an old machine but probably due to the hard drive, the thing that really makes a difference on 'snappiness' in modern computers is the SSD they tend to have which speeds up all the small tasks. Sure faster processors and RAM help but primarily with large tasks such as bulk export or video editing.

Difficult to change a HD on an iMac though...
 
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