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imac275

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Mar 24, 2013
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I am about to receive a base model 2017 iMac 27 with a 512GB SSD.

I am trying to decide on how much RAM to buy to add to the 8GB that is fitted. I had 24GB in my 2012 iMac and never noticed any problems. My most intensive uses are light photo and video editing. Would going to 32/40GB really make a noticeable difference or should I just save the cash?
 
Thanks, I think I'll buy the 16GB to take it to 24GB in total.

I hadn't even thought about RAM last time, but when I received my 2012 iMac, even scrolling quickly through RAW files in iPhoto gave me the beach ball after a few seconds. The 24GB solved that and I haven't come into any problems since.
 
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24 GB will likely be plenty for what you describe.

I got 24 GB as well, and for my usage it will likely last the life of the machine. And if it is not sufficient say 5 years from now then I’ll upgrade then... or else buy a new machine.

P.S. For me 6-8 GB is usually sufficient for me for my MacBook today in 2017... so I got 16.
For me 10-12 GB is usually sufficient for me for my iMac today in 2017... so I got 24.
 
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If you have to ask, then the answer is a hard no. I do 4k video editing, lightroom, and photoshop HARD all day long and never get close to using the full 24 gigs I have. Ram gets cheaper every year so instead of buying it now, wait till you need it and you can get far more bang for your buck. Anything beyond 24 gigs is overkill for 99% of users who own an Imac. Anyone who truly needs more than that is going to have much bigger bottlenecks in their workflow.
 
See, I disagree...

I have a Mac Pro, and it made a significant difference when I upgraded from 16 to 64GB. I use Lightroom, Photoshop, Photomatix, Bridge and MS Office, and usually all of it running at the same time, and I can definitely see/fell the difference. I also have a MacBook Pro with 16GB of RAM, and it is much slower generally when I have that many applications open.

iemcj is right though, RAM is constantly getting cheaper, so buy it when you need it.
 
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Hmm. Bridge, and office are fairly light ram wise. Photomatix I haven't used in a few years now that photoshop cc has a great hdr suite so I can't comment on that.
 
I think that Photoshop is struggling when I have more than a few images for HDR, especially at 7+... I also do a fair bit of merging, and again the amount of RAM makes a difference. I am not much into video editing, so can't comment on that.
 
If you have to ask, then the answer is a hard no. I do 4k video editing, lightroom, and photoshop HARD all day long and never get close to using the full 24 gigs I have. Ram gets cheaper every year so instead of buying it now, wait till you need it and you can get far more bang for your buck. Anything beyond 24 gigs is overkill for 99% of users who own an Imac. Anyone who truly needs more than that is going to have much bigger bottlenecks in their workflow.
You may still experience a performance boost, as macOS now uses all available RAM as a RAM disk. Just for example, I have 32 GB of RAM. Right now I have ~21 GB as "memory used," of which 18 GB is app memory (which could be removed from RAM) and only about 2.5 GB as wired memory (which absolutely has to stay in RAM). Less than 1 GB is compressed. ~9 GB is marked as "cached files." I'm using a SSD as my primary drive so you could argue that those 9 GB of cached files being in RAM isn't as noticeable a boost as if I were using a traditional HDD, but it's still faster.

Not that I'd advocate running out to max out your system's RAM, but it's probably worth it to get as much as you can comfortably afford, rather than taking a hard look at exactly how much you need and not going beyond that.

Regarding pricing, RAM is one of the few technology components that don't always get cheaper with time. There's a bit of a valley curve with the pricing, where it starts out expensive, gets cheaper and cheaper... but then becomes more expensive again as newer RAM technologies come out and production shifts over to the new modules. Just as an example, my DDR3 16 GB RAM kit was a bit under $110 when I bought it in 2015, and occasionally it could be had for cheaper. I checked it just now, when DDR4 RAM is the new standard, and the same kit is now selling for a bit over $130. I've noticed the same trend when checking over older RAM for previous systems.
 
I would go with the 24GB you had last time around as those applications will be handled by that amount. 8GB is not really sufficient. If you were into publishing, graphic design and say Quark Express, would suggest 64GB.
 
I would recommend upgrading to 24gb to start. This is cost effective because you are using the two available slots without removing what came in the Mac. Than in the future if you need more you can replace the 2x4gb that came in the Mac with 2x8gb and not mess with what you already upgraded.

Memory management will utilize all the RAM in short order. Open activity monitor and add Memory Used + Cached Files, it will likely equal Physical Memory after using the Mac for an hour or so.

Screen Shot 2017-08-22 at 1.39.01 PM.png


The way it works is if you open a file/program its loaded into RAM. When you close it, it stays in RAM but labeled as Cached. Open something else and Cached files are purged to make room for the new file/program.

If you can't see where this is going, the more stuff that can remain cached the faster it will reopen and be ready for use in the future. With an unlimited amount of RAM you can essentially make a RAM disk of sorts (obviously different and not possible but just for simplification). Because of this it makes it difficult to have "too much", however you'll have diminishing returns on investment.

If your run out of RAM (memory used - physical memory < a new file/program that is opened) memory management will use swap (the SSD in your case). And while and SSD is fast its still magnitudes slower then RAM. Swap usage should be avoided. The memory management in MacOS (all modern OS's for that matter) use compression to help avoid swap usage. While compression isn't bad its still nice to minimize its use if possible.

There are some caveats of course. If you turn your iMac on, do something, then turn it back off you may not leverage all the RAM installed. And with the speed of Apples SSDs performance gains may not be too noticeable vs the massive differences noticed with HDDs.
 
Knowledge is power. Open Activity Monitor and leave it open. Watch the contents of the Memory tab. As long as the Memory Pressure graph operates consistently in the green, you have enough RAM.

Memory pressure graph will, like you said, let you know if you have enough RAM. However just "enough" isn't always optimal. The Memory Pressure graph is only tracking Memory Usage (files/programs actively allocated to memory) not cached.

For example, if I open Gimp right now I know it will open near instantly since I was recently using it and its still likely cached in RAM. If I had 8gb of RAM it would likely have been purged and need to be loaded from the HDD, which is much slower. Since nothing else I'm running is using is in direct competition for memory both graphs will remain green.
 
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Memory pressure graph will, like you said, let you know if you have enough RAM. However just "enough" isn't always optimal. The Memory Pressure graph is only tracking Memory Usage (files/programs actively allocated to memory) not cached.

For example, if I open Gimp right now I know it will open near instantly since I was recently using it and its still likely cached in RAM. If I had 8gb of RAM it would likely have been purged and need to be loaded from the HDD, which is much slower. Since nothing else I'm running is using is in direct competition for memory both graphs will remain green.

A good point, but the question becomes, how useful is it to have this kind of additional capacity? If you're constantly switching apps, it may be more meaningful than if you tend to work within a handful of apps at a time. It may be less meaningful if you have Flash storage than a spinning HDD, etc. The trick is to spend money where you can get the most benefit. The original question is "should I get more than 24 GB RAM?" Considering the usage example, the money spent on 32 GB RAM might be better spent in some other way.
 
A good point, but the question becomes, how useful is it to have this kind of additional capacity? If you're constantly switching apps, it may be more meaningful than if you tend to work within a handful of apps at a time. It may be less meaningful if you have Flash storage than a spinning HDD, etc. The trick is to spend money where you can get the most benefit. The original question is "should I get more than 24 GB RAM?" Considering the usage example, the money spent on 32 GB RAM might be better spent in some other way.

Definitely, that is why I keep mentioning diminishing returns. And since you can easily upgrade the RAM yourself getting things that are much more difficult/impossible to upgrade down the road should take priority on initial purchase namely flash storage.

I was more or less sticking strictly to the topic of this thread since the OP already decided on the base model with 512gb SSD and is buying the RAM to add themselves.

IMO Flash storage should be the focus of any user looking to purchase a computer that wants a noticeable increase in performance or just a zippy machine in general. But if you already have a HDD and leave the machine on all the time an easy way to increase performance is add more RAM, even an amount excessive for your use. For example, I have a iMac with Flash storage at work, and 1tb HDD at home. With 24gb of RAM in my personal iMac I generally can't tell the difference unless I reboot it. After a reboot its a total turd until HDD activity has "settled down" and I've run the majority of my commonly used programs. Thankfully MacOS is a good enough OS that reboots aren't required very often.
 
I am about to receive a base model 2017 iMac 27 with a 512GB SSD.

I am trying to decide on how much RAM to buy to add to the 8GB that is fitted. I had 24GB in my 2012 iMac and never noticed any problems. My most intensive uses are light photo and video editing. Would going to 32/40GB really make a noticeable difference or should I just save the cash?
to me save get a raid ssd external. :p.
 
24gb seems to be a sweet spot for me. I'm an attorney generally living in office and Acrobat Pro, don't do any photo editing or video editing worth mentioning and I'll stand behind the first sentence.

I keep seeing all these comments about how 8gb is enough for productivity users and I'll tell you I'm regularly using 12-16gb of memory on an average workflow. When I really crank it up I get up around 20 or more. However, I've never needed any swapping to occur so I think more than 24 might be overkill.

Generally I'll have a couple of Word files open, iTunes playing something in the background, Mail, a few finder windows and Acrobat with 3-10 tabs, as well as Safari with a tab or two. Unfortunately for those saying close tabs that's not reality as you're constantly jumping back and forth cross referencing things.

While productivity is obviously not near as intensive as some of your graphics pros work out there, there is still a need for a decent amount of ram. I have last years m7 MacBook and I keep it light on that machine and I'm still almost always maxing out my ram.
 
24gb seems to be a sweet spot for me. I'm an attorney generally living in office and Acrobat Pro, don't do any photo editing or video editing worth mentioning and I'll stand behind the first sentence.

I keep seeing all these comments about how 8gb is enough for productivity users and I'll tell you I'm regularly using 12-16gb of memory on an average workflow. When I really crank it up I get up around 20 or more. However, I've never needed any swapping to occur so I think more than 24 might be overkill.

Generally I'll have a couple of Word files open, iTunes playing something in the background, Mail, a few finder windows and Acrobat with 3-10 tabs, as well as Safari with a tab or two. Unfortunately for those saying close tabs that's not reality as you're constantly jumping back and forth cross referencing things.

While productivity is obviously not near as intensive as some of your graphics pros work out there, there is still a need for a decent amount of ram. I have last years m7 MacBook and I keep it light on that machine and I'm still almost always maxing out my ram.
Yeah I hear ya.

Others will argue that many even with similar usage as yours would be fine with 8 GB, given Apple's memory management techniques and memory compression. While that is somewhat true, I also think that 16 GB gives way more breathing room for not only future memory usage increases, but also for those edge cases where memory usage gets significantly higher. An example would be your usage AND the occasional time you might add a couple of extra applications and several more browser tabs etc. Most people don't have the exact same usage every single day for the rest of their computers' lives.

For myself, 6-8 GB is actually usually OK for a laptop, but getting 8 GB just seems like cutting it too close when I like keeping my laptops for 5 years. My rule of thumb in that sort of scenario is that if you usually need 6-8 GB for a computer now, then get 16. If you usually need 12-16, then get 24. This year I went with 16 GB for my MacBook Core m3, and 24 GB for my iMac Core i5 7600.
 
24gb seems to be a sweet spot for me. I'm an attorney generally living in office and Acrobat Pro, don't do any photo editing or video editing worth mentioning and I'll stand behind the first sentence.

I keep seeing all these comments about how 8gb is enough for productivity users and I'll tell you I'm regularly using 12-16gb of memory on an average workflow. When I really crank it up I get up around 20 or more. However, I've never needed any swapping to occur so I think more than 24 might be overkill.

Generally I'll have a couple of Word files open, iTunes playing something in the background, Mail, a few finder windows and Acrobat with 3-10 tabs, as well as Safari with a tab or two. Unfortunately for those saying close tabs that's not reality as you're constantly jumping back and forth cross referencing things.

While productivity is obviously not near as intensive as some of your graphics pros work out there, there is still a need for a decent amount of ram. I have last years m7 MacBook and I keep it light on that machine and I'm still almost always maxing out my ram.

I'm surprised you need 24 GB RAM. I'm a developer for a living and my iMac has 16 GB RAM, and no matter what I am doing throughout the day the memory pressure always stays green and probably never exceeds 40% in the graph unless I have several VMs running.
 
Yeah I hear ya.

Others will argue that many even with similar usage as yours would be fine with 8 GB, given Apple's memory management techniques and memory compression. While that is somewhat true, I also think that 16 GB gives way more breathing room for not only future memory usage increases, but also for those edge cases where memory usage gets significantly higher. An example would be your usage AND the occasional time you might add a couple of extra applications and several more browser tabs etc. Most people don't have the exact same usage every single day for the rest of their computers' lives.

For myself, 6-8 GB is actually usually OK for a laptop, but getting 8 GB just seems like cutting it too close when I like keeping my laptops for 5 years. My rule of thumb is that if you usually need 6-8 GB for a computer now, then get 16. If you usually need 12-16, then get 24. This year I went with 16 GB for my MacBook Core m3, and 24 GB for my iMac Core i5 7600.

I think 16gb would be solid for the Macbook, my 2016 m7 rarely if ever gets CPU bottlenecked, it's always the system memory. Someone using an iMac I would assume wants more flexibility though and thus it would make sense to have plenty of Ram and not too little.
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I'm surprised you need 24 GB RAM. I'm a developer for a living and my iMac has 16 GB RAM, and no matter what I am doing throughout the day the memory pressure always stays green and probably never exceeds 40% in the graph unless I have several VMs running.

I thought maybe I was just being ridiculous too when I ordered the ram kit, but then a couple weeks in and keeping an eye on the status with MONIT and it seems to have been the right call.

I think what those who don't do heavy work in Adobe may not realize is when you are looking at documents that are sometimes 10 pages and sometimes hundreds if not a thousands of pages, they're always OCR'd to make them useable and thus the file sizes get massively inflated.
 
I'm surprised you need 24 GB RAM. I'm a developer for a living and my iMac has 16 GB RAM, and no matter what I am doing throughout the day the memory pressure always stays green and probably never exceeds 40% in the graph unless I have several VMs running.
running iOS simulator and android emulator yesterday + Spotify + visual studio code.. 6 to 7 GB.. There is some mistake thinking if you had more ram, if not used then what the used of it.. Windows also been spoil... Java the worst. garbage
 
24gb seems to be a sweet spot for me. I'm an attorney generally living in office and Acrobat Pro, don't do any photo editing or video editing worth mentioning and I'll stand behind the first sentence.

I keep seeing all these comments about how 8gb is enough for productivity users and I'll tell you I'm regularly using 12-16gb of memory on an average workflow. When I really crank it up I get up around 20 or more. However, I've never needed any swapping to occur so I think more than 24 might be overkill.

Generally I'll have a couple of Word files open, iTunes playing something in the background, Mail, a few finder windows and Acrobat with 3-10 tabs, as well as Safari with a tab or two. Unfortunately for those saying close tabs that's not reality as you're constantly jumping back and forth cross referencing things.

While productivity is obviously not near as intensive as some of your graphics pros work out there, there is still a need for a decent amount of ram. I have last years m7 MacBook and I keep it light on that machine and I'm still almost always maxing out my ram.

One key factor to consider - the OS will max whatever RAM you have. Chances are excellent that most of the RAM-resident processes you see in Activity Monitor are inactive - they won't be flushed from RAM until you run out of physical memory. Only at that point does the OS start killing inactive processes to make room for new processes. The basic philosophy is, "Don't remove something you may need again, so long as the space isn't needed for something new."
 
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One key factor to consider - the OS will max whatever RAM you have. Chances are excellent that most of the RAM-resident processes you see in Activity Monitor are inactive - they won't be flushed from RAM until you run out of physical memory. Only at that point does the OS start killing inactive processes to make room for new processes. The basic philosophy is, "Don't remove something you may need again, so long as the space isn't needed for something new."
What I don't understand is why some people are so quick to upgrade their iMacs to crazy amounts like 40 GB, yet so many others skimp on their laptops with 8 GB.

It seems the common statements here are:

"8 GB is enough for your MacBook, because macOS is very good for memory management and uses memory compression."

vs.

"I just ordered my new iMac with 8 GB RAM, and have another 32 GB of RAM on order from Amazon, and I'm so excited!"

That just seems odd to me. If anything it usually makes the most sense to lean toward more RAM up front with the laptops because you can't add RAM later, whereas with the 27" iMacs you can upgrade at any time, and potentially for less money later.

As mentioned, I went with 16 GB on my MacBook, and 24 GB on my iMac. I'd say for most users who have 40 GB, it is way overkill for them. Yes, some users need 40 GB, but the vast, vast majority don't, yet a bazillion users in the iMac forum have 40 GB.
 
What I don't understand is why some people are so quick to upgrade their iMacs to crazy amounts like 40 GB, yet so many others skimp on their laptops with 8 GB.

It seems the common statements here are:

"8 GB is enough for your MacBook, because macOS is very good for memory management and uses memory compression."

vs.

"I just ordered my new iMac with 8 GB RAM, and have another 32 GB of RAM on order from Amazon, and I'm so excited!"

That just seems odd to me. If anything it usually makes the most sense to lean toward more RAM up front with the laptops because you can't add RAM later, whereas with the 27" iMacs you can upgrade at any time, and potentially for less money later.

As mentioned, I went with 16 GB on my MacBook, and 24 GB on my iMac. I'd say for most users who have 40 GB, it is way overkill for them. Yes, some users need 40 GB, but the vast, vast majority don't, yet a bazillion users in the iMac forum have 40 GB.

Unfortunately I don't believe that a ram upgrade was even an option on the 2016 Macbook.
 
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