That arrangement is dual channel. You put the new RAM in its place but you just need to make sure it’s in correct dual channel config.What makes the stock location remaining with the factory RAM critical?
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40 GB of RAM worth it?
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I just posted testing results in another thread (What RAM to buy to update new iMac launched today?), after receiving my order (32GB Corsair Vengeance Performance Memory CMSX32GX4M2A2400C16) from Amazon today. The result shows using 32GB Corsair alone has the best scores in GeekBench and CineBench. The key is due to better memory latency. I decide to use 32GB Corsair only, and sell Apple's original 8GB.
What makes the stock location remaining with the factory RAM critical?
RAM should be in matched pairs. The stock RAM is already in a matched pair, so as long as one doesn't move those out of a matched pair, adding another matched pair there will be no issues with memory arrangement.
Yes, but that's because you are using a different memory speed, not because of the RAM channel matching.
However, even if you were to keep the Apple RAM and use it, and if you actually needed that much RAM, 40 GB would be faster than 32 GB. The benefits of faster latency are minor. The benefits of more RAM in systems that need that much RAM is huge.
Mind you, I suspect you'll never max out the 32 GB RAM you have so that last statement wouldn't apply. However, probably the best bang for the buck for most people (but not all people) would be to buy another 2 x 8 GB for a total of 32 GB, at Apple's stock memory latencies.
Another thing to note is occasionally with some third party RAM, the iMac will drop down to 2133 MHz until you take out the 2400 MHz Apple RAM. This type of behaviour has never been a problem with Crucial RAM.
The other weird behaviour is if you get RAM that is faster than Apple's specs, sometimes the Mac won't boot at all. This is why I prefer just getting Crucial RAM, because Crucial always just matches the exact Apple specs. Same speed, same configurations, and same latencies. While you may give up 1-2% of performance if it works, you're guaranteed compatibility, and you don't have to throw away your old RAM.
Furthermore, companies like Crucial are top tier. Crucial aka Micron is the actual RAM manufacturer.
Just a note, you listed the wrong person in that quote.
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So if I buy this RAM for my iMac 2017 i7:
http://eu.crucial.com/eur/en/imac-(retina-5k,-27-inch,-2017)-imac18,3/CT10559861
and just place it in the empty slots, it's ok? (total 40gb)
Working now on 8gb and really need the upgrade.
http://eu.crucial.com/eur/en/imac-(retina-5k,-27-inch,-2017)-imac18,3/CT10559861
and just place it in the empty slots, it's ok? (total 40gb)
Working now on 8gb and really need the upgrade.
Sounds like possibly overkill to go to 40 GB if you can actually work with 8 GB.
I went with 24 GB myself.Also, there is another kit that isn't specifically labeled as Mac-specific, but it's the same RAM. It's a bit cheaper, but probably only by a few pounds.
Crucial ram is the same as apple ram both with 2400 and cl 17.
Apple ram should be in slot 1-3 so just put your crucial ram in 2-4.
ram like hyper x have better cl, that's why one should consider removing apple's ram
I ordered Ballistix Sport from Crucial. It arrived today- 32GB Kit. I've been told on these boards it works fine with the new iMacs, but I am concerned it states on the box it's for gamers. Does that mean it's slightly faster then the RAM already in the computer? I don't want the two to mess with each other.
So what happens if you move your stock Apple DIMMS to 2-4 and put your new 16g DIMMS in 1-2?
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Agree. I removed my (2) stock 4g DIMMS and installed (2) 16g DIMMS.
Nothing. Since the cpu is dual channel the ram needs to work on the same channel.So what happens if you move your stock Apple DIMMS to 2-4 and put your new 16g DIMMS in 1-2?
As long as you don't put in channel 1 apple ram and channel 3 the new ram it will work without problem.
Just check after boot if the ram works at 2400 or 2133. In the latter remove the apple ram.
You can't really have too much RAM. Memory management will utilize all of it over time. You will have diminishing returns on investment though.
To determine how much you need you'll need to look at the apps you use. I also go a bit heavy on the RAM so what I do is start with 8gb which will cover MacOS + its core apps like messages, safari, mail, iTunes. Then ADD app requirements so for example if you are using photo editing software the recommends (not minimal requirements) 4gb RAM I would go with 12gb, if you multitask that piece of software with another that recommends another 4gb then I would want 16gb total.
The memory management of MacOS can sort this out but the goal is to avoid Swap files and minimize memory compression.
My advice is if you can comfortably afford more RAM than go for it. If you need to debate it than don't, and keep in mind you probably wouldn't see a real world difference anyway. Other reasons to consider more RAM is if you have a HDD or Fusion (to try to further limit swap use) and if you leave your Mac on 24/7 since cached data will stay cached.
If my use which includes light photo editing and video editing I can't tell difference over 20gb RAM. Unless you have specific task that require more RAM its unlikely you'll have too much real world benefit going with 40gb over 32gb.
Yeah, that's why I went with 24 GB. I have a friend that is a pro designer and 24 GB is fine for him too, and he works at his desk all day long doing this stuff. I suspect it could make sense for him to go higher, if he has a few unusually large projects going, but for the rest of us 24 GB is usually more than fine.
On RAM and Hard Drive space, I frequently remind myself, regarding my first Apple IIE computer purchase. Wherein, the Apple salesperson unequivocally stated, that I would never in my lifetime, need more than an 80mb hard drive and 2mb of ram! This computer would last for ever.
I often wonder what her thoughts are now regarding her statement then, versus now!!??!!
I often wonder what her thoughts are now regarding her statement then, versus now!!??!!
Would depend on what software you run and how many applications you have open. Apple wouldn't be selling 8gb machines if it presented an awful experience for typical users. I use PS which, especially if you have several layers open, can use a lot of memory. So I knew I wanted more than 8gb. I think 16gb would be more than sufficient for the vast majority of users. I debated adding 16, to go to 24, or 32, to go to 40. I went for the 32 but largely because ram prices are pretty inexpensive right now and I figured, why not? The system will report using a lot of ram even when I don't have a lot of stuff loaded; but the memory pressure is low. In an actual is it providing value, I'd guess that adding 32gb probably is not the best value, for most people. Given current prices, adding 16gb to get up to 24gb just seems like a sensible thing to do.
MMMMMMmmmmmmmarketing!
Otherwise, it’s a meaningless statement.
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There are many situations where more RAM = better.
The big one is that memory leaks are a fact of life. If you are on the internet all day, browsers and web sits, plugins, certain apps and their plugins... Nothing quite like reading an update list for an app and seeing that every one included memory leak fixes.
When my iMac had 24GB, I stood a good chance that it would freeze by the end of the day. A RAM check would show less than 300MB free. Going to 32GB put a stop to that as long as I rebooted every day.
My wife’s machine uses around 12G of the 20G installed after a week or so— the main culprit being Word 2008 but Quark Express has a bit, too. She doesn’t run some of my AV apps, of course.
Running sudo purge in Terminal will free up some RAM but not like a reboot.
Having recently bought an iMac Pro with 128GB on board (used machine at a great price), I don’t think I have much to worry about in that regard. I will test regularly to see because I’m curious. It will be hard not to reboot as part of my morning routine—I like that it gets up, running and logged into 150 web sites in 45 seconds (my 2010 took around 90 after I installed an SSD; 20 minutes with the original HDD). Anyway, it’ll be interesting to see how much I use after a week or so or if the leaks in my routine are enough to choke this beast.
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Realistically I probably only needed 24-32GB but it came with 8GB and if I ever want to upgrade it to 64GB years down the road then I can just swap out the 4GB sticks for more 16GB sticks. I think this thing is going to last a long time and even if they stop supporting Intel chips and it doesn't get any more software updates it will still be a great backup machine, Linux server or even media device for my workshop. For me I just didn't want to ever feel it slow down if I could help it, even when multitasking like a fool, and adding 32GB wasn't really expensive so why not?
RAM is a high bandwidth storage device, the only thing that will see improvement for all users is latency, but your memory will usually be bottlenecked by the highest latency stick so if you have low latency memory you might want to swap completely instead of putting in additional memory. If you have a program that preload a lot 40gb will see improvement, but most heavy browsers or games don't properly utilize that much extra space. In hosting and editing workloads where the cost would quickly be made back or situation where you have a 32 gb system and are seeing all your ram used upgrading is obvious, but as others have said it can slow your system down to throw overpowered components at consumer hardware
I apologize for bringing back a dead thread
I apologize for bringing back a dead thread
Run iStat for about 30 days. Collect the history of your swap memory usage. If it consistently larger than 25% of your current installed RAM, then an upgrade is definitely worth while.
Suppose that you have 16GB of RAM. In the past 30 days there were at least 15 day occurrences in which your swap memory usage has gone beyond 4GB. That means you would definitely benefit from a RAM upgrade.
I have a Late 2009 27" iMac and it had 4 GB and started running my programs and was 1 GB of swap. I upgraded to 12 GB and my memory usage went up to about 11+ GB so I ordered enough RAM to get up to 16 GB. The Late 2009 iMac has a Core 2 Duo and isn't fast though it's fine for watching YouTube and mp4 videos. So I took a 2015 MacBook Pro 15 and hooked it up to a 25" QHD monitor and set it up next to the iMac and moved everything except for YouTube and VLC over to the MacBook Pro. That got rid of the swap on the iMac but I have a small amount of swap on the MacBook Pro now.
So all new systems I buy will have at least 32 GB of RAM.
My work PC has 64 GB of RAM and typically uses about 29 GB of RAM though it will cache several GB more. And it allows me to run additional Virtual Machines if I want to play around with new operating systems. My Windows PC has four slots and I'm only using two of them so I could upgrade to 128 GB or even 256 GB if I need it down the road.
I expect Apple's PCs in 2021 to make Intel-based PCs obsolete.
So all new systems I buy will have at least 32 GB of RAM.
My work PC has 64 GB of RAM and typically uses about 29 GB of RAM though it will cache several GB more. And it allows me to run additional Virtual Machines if I want to play around with new operating systems. My Windows PC has four slots and I'm only using two of them so I could upgrade to 128 GB or even 256 GB if I need it down the road.
I expect Apple's PCs in 2021 to make Intel-based PCs obsolete.
Except Apple Silicon computers won't likely to have upgradable RAM, thanks to the Unified Memory Architecture.