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40 GB of RAM worth it?
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Rarely, actually. Memory usage in Mac OS is so well managed that most of the time the stock 8GB is fine for people. An SSD makes life with that little ram better, too.
But if you need it, you will know it. Watch your "memory pressure" in the Activity Monitor.
But if you need it, you will know it. Watch your "memory pressure" in the Activity Monitor.
You need to list out your apps.
I went to 40 and it was cheap and I have so much more room now for my workflow.
I went to 40 and it was cheap and I have so much more room now for my workflow.
The more RAM you install, the more macOS will use it to try and improve performance. As mentioned above, in Activity Monitor > Memory if Memory Pressure is high and/or the system is paging/swapping to the SSD/HDD (Swap Used) then you would benefit from adding RAM. Also, if performance in general is poor (slow app launches, spinning beachball, etc) then it could be RAM deficiency-related. 8GB is not a lot but if you have minimal apps running and don't use VMs, etc then it is possible for it to suffice.
RAM is a bit like hard disk space. You don’t really want to run it close to the bone. I know I wanted 32GB for my iMac and so it made sense to get 2X16Gb modules which added up to 40. I can’t see me ever needing to max it out but I also didn’t want to waste the preinstalled 8. So, 4X8GB wasn’t what I wanted. Currently, I’ve been running Final Cut Pro X, Motion and a few Safari tabs simultaneously and not really going below 20GB. However, your usage might differ to mine and so you might use even less. But, 40 is about right for me. 68 would be a total waste of money.
if you read the other thread about ram on the new imac you will see that if you bought faster ram than the apple one you will only get lower performance by using both ram.
What kit did you bought?
Of course. What's 40, all Apple computers, from the top tier Mac Pro to the nifty portable MacBook should have come with 64GB RAM standard already.
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If you need to ask, then no.
If you're an average user 16GB is plenty. If you run a lot of pro software and virtual machines, 32GB will improve performance. 32+GB is in most cases, a waste of money.
If you're an average user 16GB is plenty. If you run a lot of pro software and virtual machines, 32GB will improve performance. 32+GB is in most cases, a waste of money.
Up to a limit. A 10 GB file cache tends to be highly speculative.
Programs may not be written to take advantage of extremely large amounts of memory. I'd think that fsck_hfs would like to use more than 3GB of memory (to store deeper trees and other more elaborate data structures), but no.
Safari, with a couple dozen tabs might use 8GB.
From what I can tell. Abbyy Finereader, divides the workload among 4 processes, each using a gigabyte... Might be different with a hyperthreaded processor, or a cpu with more than four cores...
Photoshop, and a few other adobe products like to grab enormous amounts of ram for themselves, but whether it amounts to a speed advantage depends on the circumstances.
Remember, good programmers are careful about memory usage. A scheme that deliberately uses more memory in order to produce a speed advantage must be carefully profiled.
Virtual machines tend to require the most amount of memory, but then you might have to consider whether the VM really needs all 8 GB, or 16 GB, or can do the job with 4 GB...
40 GB is an enormous amount of RAM, and if it ends up being slower than the stock 8GB due to a timing mismatch you'd probably notice the slowdown, before you'd notice the effects of having more.
Wait what?? How is 40GB going to slow down your computer more then the 8GB? That's not making sense at all. Timing mismatch? Never heard of it. I'm not at all trying to come off crass, I just need further insight. Especially if I'm about to spend money on all this ram and it turns out I don't need to.
RAM has speed and latency figures. This "timing" that we talk is latency, also otherwise known as CAS. Speed is 1600MHz 1866MHz 2133MHz etc.
What you need to do is match all the sticks you stick in your computer. Get the lowest possible latency with the highest possible speed your computer can support.
Now, buying higher latency means observable snappiness differences can occur. More than the perceptible difference in bus speed. A slower latency will be more noticeable than a faster speed.
So in other words, don't get the 16X2 sticks (32GB) to add to the preinstalled ram Apple has, because they put in 2X4GB? I'm still not following, sorry. Everyone has reported they added RAM with the 32GB kits and their machines run just fine. This is just confusing.
Could you post the photos of both sides of the sticks you are currently using, and the sticks you wish to buy/ have bought already?
Do not scrimp on RAM purchases from a quality company. Go OWC or Crucial Mac and you will get guaranteed compatibility.
Do not scrimp on RAM purchases from a quality company. Go OWC or Crucial Mac and you will get guaranteed compatibility.
I'm going with the Ballistix Sport LT: https://www.amazon.com/Ballistix-16...1DGOF3E4?_encoding=UTF8&tag=macrumors-20&th=1
The Ballistix works. I'm using it in addition to the Apple stock RAM. I can recommend it highly.
Thanks! You were the reason I researched it more and it looks splendid
Could you verify the speed of the memory? (using About This Mac|System Report|Hardware|Memory)
The ballistic & hyperX ram are faster than apple ram (cl14,15 for hyperX, cl17 for apple ram) so using both will slow down the faster one. Some people had also speed reduced to 2133 instead of 2400. This is why it is better to remove apple ram if you buy 16x2 kit and if it is faster than apple (i think crucial is the same as apple both in speed and cl).
If the Apple RAM is slowing down my Ballistix the benchmarks don't show it. All 40GB, including the Apple RAM is running at 2400MHz. Take it from someone who is actually using it.
The 2133MHz problem with Hyper-X RAM is due to the fact that the Kingston RAM is overclocked.
I'm not sure 40 Gb is cost effective. I might be inclined to go with an additional 16 (2x8) for 24 Gb total. On the other hand if you can get a 2x16 kit for a reasonable increment, and it's the right RAM, I can't think that it would hurt.
(Technically, additional RAM isn't free as far as the OS is concerned. Tracking RAM usage requires page tables and other data structures which grow with physical RAM. I don't know how OS/X does it, but any rational OS will arrange things so that the physical RAM data structure time overhead is minimal if you aren't actually using it for anything useful.)
(Technically, additional RAM isn't free as far as the OS is concerned. Tracking RAM usage requires page tables and other data structures which grow with physical RAM. I don't know how OS/X does it, but any rational OS will arrange things so that the physical RAM data structure time overhead is minimal if you aren't actually using it for anything useful.)
What do you mean it isn't free? If I want to add to the additional ram included by Apple, the slots allow it. The OS will certainly recognize it, and thus I should have 40GB of RAM.
Explain this "Isn't Free" one, because I'm hearing all sorts of crazy theories today.
All I mean is that the OS has to be aware of the RAM that exists. Typically this is done via some sort of data structure that grows with physical memory. The more RAM, the larger this data structure is, and done naively, the longer it might take to perform operations on that data structure. A naive OS which doesn't expect large physical memory might use a data structure that is time intensive based on size. A properly written, modern OS will use algorithms that scale with physical memory actually in use, and not physical memory that exists in the hardware. I would expect that OS/X, being a modern operating system, will use a data structure and corresponding algorithms that scale with memory in use, and adding memory beyond what can be effectively used will have little to no effect.