Help me decide: 18GB or 36GB of RAM?

[baryon]

I have an Intel i9 16 inch MBP with 32 GB of RAM. I don't think I really needed 32GB but wanted to "future proof" the machine which I think was a bit of a waste of money at the time.

I use my current MBP for grading in DaVinci resolve, often working with 6K raw footage from Blackmagic cameras, but Activity Monitor says Resolve only uses 4-5 GB of memory during those times.
I also use Stable Diffusion with Automatic1111 and although it's slow, I do like to be able to run it when I need it. I don't know if it would run the same with less RAM. I actually wonder if 18 GB of unified RAM is better for the GPU than 8 GB vRAM + 32 GB CPU RAM?
But I don't really do any of this as a living, it's just nice to be able to do it.

I'm thinking of upgrading to a 16 inch M3 pro, though my current machine is still running great. I have never used M series Macs, but I only ever hear good things about them. I get the impression that memory management is very different on them. I wonder if 18GB is enough for what I want to do, as I really want to avoid spending this much money on 36GB if I don't need that most of the time, this thing is already very expensive as it is.

So what would you say, does anyone here have a 16GB M1 or M2 machine that you use for Stable Diffusion and color grading in Resolve? How does it run?

 

[raythompsontn]

In my opinion 18 Gig should be fine. But it is your choice and your money. If you can afford 36 Gig, go for it. More is never going to be a bad thing when purchasing memory. The only downside is cost and that is a decision only you can make.

 

[ColdCase]

I've ran out of M1 16Gb RAM (slows down) when several tabs are open to demanding web sites or when 3 apps are open and processing. Fine with typical surfing and a single app. Haven't noticed slow downs with 32Gb yet regarless of the number of tabs oen.

 

[gadgetfreaky]

I run out of memory all the time on my 16gb. But my programmer friend runs out on 32 all the time...I'd say err on teh side of more. If you are a dev..do way more mem. memory management on Macs has gotten really terrible

 

[0423MAC]

18GB will likely be fine, but the best way to come to a decision would be to keep your activity monitor open in the background and take a look at the memory pressure every now and then while you work.

What year is your Intel Mac? How often do you tend to upgrade your machines?

 

[OrenLindsey]

Like it was said above, I think the only downside is cost. It gives you the potential for a lot more power and performance. Basically, it raises the ceiling for what your computer can do. Your device will not be bottlenecked by the memory.
For stable diffusion especially, you want a lot of memory. And color grading will definitely want a good amount.
I would lean towards getting more, but that $400 price increase can be a pretty big deal.

 

[ignatius345]

Kind of off topic, here, but for many years RAM has come in multiples of 4 and 8 (4, 8, 16, 24, 32).

What's with the multiples of 9 (18, 36) all of the sudden? Just curious.

 

[OrenLindsey]

Kind of off topic, here, but many years RAM has come in multiples of 4 and 8 (4, 8, 16, 24, 32).

What's with the multiples of 9 (18, 36) all of the sudden? Just curious.

They threw in some extra to try to make up for the lower memory bandwidth, and to give people a reason to upgrade
Edit:

6GB chips with three memory channels.

This as well probably

 

[GMShadow]

Honestly if you're still happy with your current Mac, I'd say wait another generation and see what happens then. I'm still on the same machine (just lower spec) so I'm taking my own advice.

 

[daneoni]

36GB.

 

[ArkSingularity]

Kind of off topic, here, but many years RAM has come in multiples of 4 and 8 (4, 8, 16, 24, 32).

What's with the multiples of 9 (18, 36) all of the sudden? Just curious.

6GB chips with three memory channels.

 

[baryon]

18GB will likely be fine, but the best way to come to a decision would be to keep your activity monitor open in the background and take a look at the memory pressure every now and then while you work.

What year is your Intel Mac? How often do you tend to upgrade your machines?

It's a 2019 i9 32GB with the 8GB GPU. So quite beefy even today, the performance is totally fine, it's just that in my experience Macs begin to break down after 4 years (battery, screen, etc) and repairs are not worth it, so better sell if off while it still works. I just don't want to buy anything that's less good (smaller screen or worse performance).

Like it was said above, I think the only downside is cost. It gives you the potential for a lot more power and performance. Basically, it raises the ceiling for what your computer can do. Your device will not be bottlenecked by the memory.
For stable diffusion especially, you want a lot of memory. And color grading will definitely want a good amount.
I would lean towards getting more, but that $400 price increase can be a pretty big deal.

It's even worse where I live, equivalent of $550 for the RAM upgrade. Which I could afford if I had to, but I don't want to pay that much money unless it's absolutely necessary.

Honestly if you're still happy with your current Mac, I'd say wait another generation and see what happens then. I'm still on the same machine (just lower spec) so I'm taking my own advice.

I might do that if my machine continues to function for another year (in my experience after 4 years the likelihood of an expensive hardware failure increases a lot).

 

[GMShadow]

I might do that if my machine continues to function for another year (in my experience after 4 years the likelihood of an expensive hardware failure increases a lot).

It does depend on the computer but the bathtub curve can start to bend back up around that point (most businesses go with five years). I haven't worried as much as I just extended AppleCare+ on mine - is that an option for you, or...?

 

[OrenLindsey]

One more thing: I would not get the M3 Pro chip. It may seem like it's the shiniest and newest, but (and this is based on Apple's charts) it has about a 10-15% upgrade from the M2 Pro chip, at most, and it has LOWER memory bandwidth, which is kind of bad. It also has less performance cores, and less cores overall, which is pretty bad.

In your position, I would do one of the following: 1) buy the M3 Max chip, 2) buy a refurbished M2 Pro (they have plenty on the refurbished store if you have that in your area) or 3) wait for the M4 Pro chip
Also, If you went for option 2, you could get 32gb or even 64gb ram for A LOT less than Apple's pricing. I did that myself (that's the device I have right now) and it was well worth it.

 

[DHagan4755]

One more thing: I would not get the M3 Pro chip.

Coming from the Intel i9 he won't notice.

 

[baryon]

It does depend on the computer but the bathtub curve can start to bend back up around that point (most businesses go with five years). I haven't worried as much as I just extended AppleCare+ on mine - is that an option for you, or...?

I don't have AppleCare anymore, where I live I've had bad experiences with them taking much too long (i.e. many weeks/months) to do repairs (I can't be too long without my computer) so I'd rather just pay an independent shop if something goes wrong (battery replacement usually).

One more thing: I would not get the M3 Pro chip. It may seem like it's the shiniest and newest, but (and this is based on Apple's charts) it has about a 10-15% upgrade from the M2 Pro chip, at most, and it has LOWER memory bandwidth, which is kind of bad. It also has less performance cores, and less cores overall, which is pretty bad.

In your position, I would do one of the following: 1) buy the M3 Max chip, 2) buy a refurbished M2 Pro (they have plenty on the refurbished store if you have that in your area) or 3) wait for the M4 Pro chip
Also, If you went for option 2, you could get 32gb or even 64gb ram for A LOT less than Apple's pricing. I did that myself (that's the device I have right now) and it was well worth it.

Yeah I'm also thinking about the M2 Pro but we don't have refurbished where I live. I'm hoping that some shops might reduce the price once the M3s arrive, but as they're still selling the M1 for the same price as the M3, I don't have much hope... I'll keep an eye out for discounted M2s though.

 

[0423MAC]

It's a 2019 i9 32GB with the 8GB GPU. So quite beefy even today, the performance is totally fine, it's just that in my experience Macs begin to break down after 4 years (battery, screen, etc) and repairs are not worth it, so better sell if off while it still works. I just don't want to buy anything that's less good (smaller screen or worse performance).



It's even worse where I live, equivalent of $550 for the RAM upgrade. Which I could afford if I had to, but I don't want to pay that much money unless it's absolutely necessary.



I might do that if my machine continues to function for another year (in my experience after 4 years the likelihood of an expensive hardware failure increases a lot).

My guess is that your biggest limiting factor (if any) with the i9 would be the thermal throttling which is very hard to do on M series SOCs.

Swap CAN be an issue if you ever find yourself in a situation in where you are at a steady 16GB+ RAM utilization, but as someone who has worn out consumer and even enterprise grade SSDs I can tell you that the concerns are largely overblown. I have budget SSDs that have gone way over their estimated TBW and still work perfectly fine till this day.

 

[pgolik]

I'm following this thread with interest, as I'm facing a similar dilemma. When I bought my current MBP in 2015, I went for a higher specification. As a result, the machine served me well for almost 9 years, and while the CPU and (especially) GPU do show their age (to the point where remote zoom or google meet sessions begin to drop), my memory pressure is still mostly in the green.
I don't like changing devices often, and I'd like my next purchase ideally to last me as long as the 2015 one. I'm considering the non-binned 14" Pro MBP (mostly because it starts with 1TB storage), and I'm torn between 18 and 36 GB for RAM. If I'm in the green with 16GB on my Intel, I should be fine with 18GB on the M3Pro, but will 36GB give me more comfort 5 years down the road? My work, other than the usual Office/web/light graphics (Affinity), is mostly in rather specialized data analysis (bioinformatics) using a mixture of Python, R, and command line programs, I also play with amateur digital photography (24Mpix RAWs) and occasionally some video (4K-5K at most).
18GB should be plenty for now, but I'm seeing, in this very thread, posts about already maxing out 16GB with a few complex browser tabs (something I do a lot), so I'm concerned that it'll become tight in a few years.
I know that it's impossible to predict the future of software, but I'd like to hear more input from those who begin to feel limited by 16/18GB RAM on Apple Silicon (for something other than editing 8K video/100Mpix RAW photos, which I'm unlikely to do).

 

[caoimhe]

My current Mac is also the 2019 16” i9 and I may switch to the new 14” M3 Pro. I never trust that I won’t run out of memory I decided it has to be 36GB RAM. What is going to kill me though is losing the 8TB SSD in my current Mac and having to move a lot of files off to an external SSD, but I’m not willing to move up to the M3 Max because I can’t justify the cost. (What I won’t miss are the constant GPU panics I get on my 16”).

 

[pgolik]

My current Mac is also the 2019 16” i9 and I may switch to the new 14” M3 Pro. I never trust that I won’t run out of memory I decided it has to be 36GB RAM. What is going to kill me though is losing the 8TB SSD in my current Mac and having to move a lot of files off to an external SSD, but I’m not willing to move up to the M3 Max because I can’t justify the cost. (What I won’t miss are the constant GPU panics I get on my 16”).

I’m leaning towards 36 as well, the cost doesn’t look as bad when spread over all the years I plan to get from the machine. Also, some programs that I use assign RAM per thread, so with more cores in the CPU they’ll use more memory on M3 than on the 4 core intel. Storage is painful, I put an nvme 2TB in my current MBP, but I can live with 1TB plus cloud and external, just stop being a hoarder of old files.

 

[0423MAC]

Nothing wrong with future proofing, just understand that the Apple Silicon Mac era might look completely different than the Intel era.

I would look toward a 4-5 year cycle in terms of software updates with a few more years of security patches after that. I worry that tools like opencore legacy patcher will go the way of the dodo as Apple continues to lock down their platforms.

 

[Nicole1980]

I have an Intel i9 16 inch MBP with 32 GB of RAM. I don't think I really needed 32GB but wanted to "future proof" the machine which I think was a bit of a waste of money at the time.

Yea, this whole idea of upping specs you don't currently need, like ram - on some vague notion that it will somehow make it "future-proofed" has always seemed ridiculous to me.

And here you are, just a handful of years later buying a new machine anyway.

No matter how you configure your system, in 3-5 years the computers that are on the market will have so surpassed your machine in other ways that your tons of ram won't make it feel 'current'.

 

[Pecka]

I would never buy a new computer that has less RAM than the old one, but that's just me.

 

[Nicole1980]

I would never buy a new computer that has less RAM than the old one, but that's just me.

I would somewhat agree, unless you bought a ridiculous amount of ram the last time around (that you didn't need) foolishly thinking that would future-proof you, and now you've come to your senses and realize that a lower amount of ram would still more than easily handle all of the tasks you can ever imagine using a computer for.

 

[pgolik]

No matter how you configure your system, in 3-5 years the computers that are on the market will have so surpassed your machine in other ways that your tons of ram won't make it feel 'current'.

It doesn’t look that way with the M1 generation, still feels current enough for most. OS support is an open question, but Apple have a good track record with supporting older iPads.