7 ms·

Why do I need to select the most expensive M3 Max version (the one with 16 cores) to get 48 or 64 gigs of RAM. The M3 Max with 14 cores only allow 36 or 96 gigs

Why do I need to select the most expensive M3 Max version (the one with 16 cores) to get 48 or 64 gigs of RAM. The M3 Max with 14 cores only allow 36 or 96 gigs. Just let me choose 14 cores and 64 gigs.

stetrain 3y ago
In previous gens they had different die sizes with different physical numbers of memory controllers and connections. Guessing it's similar here. Rumor is Apple bought all of TSMC's initial 3nm production. They are probably yield limited on full featured chips.
- spookie 3y ago
  Most likely. Let's not kid ourselves, there would be more players sharing those if they felt it was worth it.
coffeebeqn 3y ago
You are in their target market of who they can really squeeze since you want something a little bit special. Their memory pricing has always been absurd. Even on an older MacBook it was often +$200 for something silly like a 16GB SODIMM that costs $50 at the store. I still think their build quality , screen quality and OS are pretty much unmatched.
- tqkxzugoaupvwqr 3y ago
  It’s worse. The configurator is labeled with a relative price upgrade but an absolute RAM size. The actual deal is +$200 for +8 GB RAM which is outrageous.
  - jonwinstanley 3y ago
    Sure, but they aren’t charging you anywhere close to cost. It’s painful for a company that size to add an option like this. Plus they know they can add a chunk on because if you’re in the market for that option, they know how much you want it.
    - turquoisevar 3y ago
      The same discussion about cost/value comes up every single time. Often, people will search for a random part that fulfills the same function, sort by cheapest, and then let their indignation run wild, completely ignoring the difference in form factor, other properties, or even quality. That said, it’s no secret that Apple adds a healthy margin and an “inconvenience” tax. In Apple’s ideal world, all people would purchase a handful of mass-produced configurations. This saves them in manufacturing costs, assembly costs, and logistical costs. Apple also spent an ungodly amount on engineering to “make more with less”. In the long run, this saves them money on lower-capacity components, especially at the quality and with the ancillary properties they're purchased. This is why spec for spec their iPhones and Macs look underpowered compared to competitors while performing the same if not better. So, from their perspective, it’s “fair” to upcharge the “spec peepers” and professionals who really need it. The latter is generally less price-sensitive.
      - quitit 3y ago
        As you've stated people will make comparisons between the cheapest bottom rung slot-in ram against what's on offer from Apple's UMA. It's naive. But even when one could just pop in your own RAM, many would still buy Apple's upgrade, which sounds insane on the surface. But there are actually pretty sound reasons for it: 1. They're buying the Mac hardware because it works. That's one of the core motivations for spending the extra to begin with.* 2. Adding ram is the gateway to unexpected crashes, such as errors that only pop up during heavy use, higher temperatures and the like. It doesn't have to be cheap either. 3. But if one is going for those cheaper components, one gets what they pay for: "mislabeled"(online fraud schemes), counterfeit, bottom-rung binned components sold as legit are par for the course. -- * A lot of brands say their products work, when they simply don't. Here's some of my own examples: I'm now onto my 3rd brand of mesh wifi routers - why? Because what's out there is garbage, even when you pay a lot for it. It's clear that there is insufficient QA on many top brands, and they simply won't acknowledge that the product they've sold you doesn't perform. I purchased one of the pricy 5k LG screens that were a total lemon, at this level of expense you don't expect school-boy errors in hardware. LG handled it poorly, both in their return and exchange options, as well as customer support and patches.
jacquesm 3y ago
Because you'll pay if you're in the market for that much memory.
stetrain 3y ago
Wild guess but if the base chip has 3 channels and the higher binned chip has 4 channels: 3x6GB = 18GB 3x12GB = 36GB 3x32GB = 96GB 4x12GB = 48GB 4x16GB = 64GB 4x32GB = 128GB
- jxy 3y ago
  But the bandwidth goes like, 100 GB/s, 150 GB/s, 300 GB/s, 400 GB/s. Given either CPU or GPU alone can't saturate bandwidth (assuming M3 the same as M1 and M2), perhaps the memory controller or the chip layout is to blame.
  - stetrain 3y ago
    Right, the two M3 Max SKUs being discussed above are the ones with 300GB/s and 400GB/s memory bandwidth. That sounds like 3 memory controllers vs 4 memory controllers, likely due to chip binning. TSMC's 3nm processes supposedly still has relatively low yields.
claytongulick 3y ago
This kind of blows my mind. I'm running the lowest spec m1 with 8 gigs of ram for my daily driver. I frequently have tens of chrome browser tabs open across multiple profiles, multiple chrome debuggers, at least two or three VS code instances, multiple high memory nodejs processes, video conferencing, screen sharing and building code all at the same time - and the thing runs smoothly without a hiccup. And does it on battery! For a full work day, at least. Weighs less than a pixie's fart. I can't even imagine the capabilities the new m3 max has with that kind of memory and power available. It's going to pinch, but I guess I'll be finding out in a few weeks.
- abhinavk 3y ago
  What's your swap used and memory pressure in Activity Monitor? Regarding Chromium browsers, I have noticed that they tend to unload tabs more aggressively these days.
- Osiris 3y ago
  I have the same one and it’s neigh unusable. The memory is constantly maxed out and it freezes frequently while swapping. I can’t use it. It’s in a drawer somewhere.
  - claytongulick 3y ago
    That's so wild - I wonder what the difference is? My m1 is so good it seriously makes me wonder if I really need to upgrade. What kind of workload are you running on yours?
lynguist 3y ago
Just get the 96G option? It is only around 100$ more for 1.5x the memory. And 1.5x the memory is worth it when you are interested in high memory applications anyway. What is your usecase, LLMs? Other AI models? Multiple large VMs? It’s always worth it to max the memory. In this case going from 64 to 96.
dwaite 3y ago
They don't just differ by cores, they have different memory bandwidth - presumably because they have different width memory busses into the SoC. Their designs, being primarily mobile-focused, are rather hard-coded to specific memory configurations.

stetrain 3y ago

In previous gens they had different die sizes with different physical numbers of memory controllers and connections. Guessing it's similar here. Rumor is Apple bought all of TSMC's initial 3nm production. They are probably yield limited on full featured chips.

spookie 3y ago
Most likely. Let's not kid ourselves, there would be more players sharing those if they felt it was worth it.

coffeebeqn 3y ago

You are in their target market of who they can really squeeze since you want something a little bit special. Their memory pricing has always been absurd. Even on an older MacBook it was often +$200 for something silly like a 16GB SODIMM that costs $50 at the store. I still think their build quality , screen quality and OS are pretty much unmatched.

tqkxzugoaupvwqr 3y ago
It’s worse. The configurator is labeled with a relative price upgrade but an absolute RAM size. The actual deal is +$200 for +8 GB RAM which is outrageous.
- jonwinstanley 3y ago
  Sure, but they aren’t charging you anywhere close to cost. It’s painful for a company that size to add an option like this. Plus they know they can add a chunk on because if you’re in the market for that option, they know how much you want it.
  - turquoisevar 3y ago
    The same discussion about cost/value comes up every single time. Often, people will search for a random part that fulfills the same function, sort by cheapest, and then let their indignation run wild, completely ignoring the difference in form factor, other properties, or even quality. That said, it’s no secret that Apple adds a healthy margin and an “inconvenience” tax. In Apple’s ideal world, all people would purchase a handful of mass-produced configurations. This saves them in manufacturing costs, assembly costs, and logistical costs. Apple also spent an ungodly amount on engineering to “make more with less”. In the long run, this saves them money on lower-capacity components, especially at the quality and with the ancillary properties they're purchased. This is why spec for spec their iPhones and Macs look underpowered compared to competitors while performing the same if not better. So, from their perspective, it’s “fair” to upcharge the “spec peepers” and professionals who really need it. The latter is generally less price-sensitive.
    - quitit 3y ago
      As you've stated people will make comparisons between the cheapest bottom rung slot-in ram against what's on offer from Apple's UMA. It's naive. But even when one could just pop in your own RAM, many would still buy Apple's upgrade, which sounds insane on the surface. But there are actually pretty sound reasons for it: 1. They're buying the Mac hardware because it works. That's one of the core motivations for spending the extra to begin with.* 2. Adding ram is the gateway to unexpected crashes, such as errors that only pop up during heavy use, higher temperatures and the like. It doesn't have to be cheap either. 3. But if one is going for those cheaper components, one gets what they pay for: "mislabeled"(online fraud schemes), counterfeit, bottom-rung binned components sold as legit are par for the course. -- * A lot of brands say their products work, when they simply don't. Here's some of my own examples: I'm now onto my 3rd brand of mesh wifi routers - why? Because what's out there is garbage, even when you pay a lot for it. It's clear that there is insufficient QA on many top brands, and they simply won't acknowledge that the product they've sold you doesn't perform. I purchased one of the pricy 5k LG screens that were a total lemon, at this level of expense you don't expect school-boy errors in hardware. LG handled it poorly, both in their return and exchange options, as well as customer support and patches.

jacquesm 3y ago

Because you'll pay if you're in the market for that much memory.

stetrain 3y ago

Wild guess but if the base chip has 3 channels and the higher binned chip has 4 channels: 3x6GB = 18GB 3x12GB = 36GB 3x32GB = 96GB 4x12GB = 48GB 4x16GB = 64GB 4x32GB = 128GB

jxy 3y ago
But the bandwidth goes like, 100 GB/s, 150 GB/s, 300 GB/s, 400 GB/s. Given either CPU or GPU alone can't saturate bandwidth (assuming M3 the same as M1 and M2), perhaps the memory controller or the chip layout is to blame.
- stetrain 3y ago
  Right, the two M3 Max SKUs being discussed above are the ones with 300GB/s and 400GB/s memory bandwidth. That sounds like 3 memory controllers vs 4 memory controllers, likely due to chip binning. TSMC's 3nm processes supposedly still has relatively low yields.

claytongulick 3y ago

This kind of blows my mind. I'm running the lowest spec m1 with 8 gigs of ram for my daily driver. I frequently have tens of chrome browser tabs open across multiple profiles, multiple chrome debuggers, at least two or three VS code instances, multiple high memory nodejs processes, video conferencing, screen sharing and building code all at the same time - and the thing runs smoothly without a hiccup. And does it on battery! For a full work day, at least. Weighs less than a pixie's fart. I can't even imagine the capabilities the new m3 max has with that kind of memory and power available. It's going to pinch, but I guess I'll be finding out in a few weeks.

abhinavk 3y ago
What's your swap used and memory pressure in Activity Monitor? Regarding Chromium browsers, I have noticed that they tend to unload tabs more aggressively these days.
Osiris 3y ago
I have the same one and it’s neigh unusable. The memory is constantly maxed out and it freezes frequently while swapping. I can’t use it. It’s in a drawer somewhere.
- claytongulick 3y ago
  That's so wild - I wonder what the difference is? My m1 is so good it seriously makes me wonder if I really need to upgrade. What kind of workload are you running on yours?

lynguist 3y ago

Just get the 96G option? It is only around 100$ more for 1.5x the memory. And 1.5x the memory is worth it when you are interested in high memory applications anyway. What is your usecase, LLMs? Other AI models? Multiple large VMs? It’s always worth it to max the memory. In this case going from 64 to 96.

dwaite 3y ago

They don't just differ by cores, they have different memory bandwidth - presumably because they have different width memory busses into the SoC. Their designs, being primarily mobile-focused, are rather hard-coded to specific memory configurations.