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My favorite quote: "It's sort of like arguing that because your electric car can use dramatically less fuel when driving at 80 miles per hour than a Lamborghini, it has a better engine -- without mentioning the fact that a Lambo can still go twice as fast."

https://www.macrumors.com/2022/03/17/m1-ultra-nvidia-rtx-309...

Right, but if I can strap two electric cars together and go as fast as the Lamborghini for less fuel, isn't that still better?
That link was about GPU power and according to the benchmarks it can't go as fast with two.
I did read the link, this indicated to me that it sort-of can:

> Apple's M1 Ultra is essentially two M1 Max chips connected together, and as The Verge highlighted in its full Mac Studio review, Apple has managed to successfully get double the M1 Max performance out of the M1 Ultra, which is a notable feat that other chip makers cannot match.

Unless you're talking about power per watt? GPU workloads are generally inherently parallelizable so performance per watt is actually what generally matters, rather than raw FLOPS.

In the analogy the Lamborghini would be an RTX 3090, and the macrumors article makes it abundantly clear the Ultra isn't even half of the RTX 3090 performance.
Right, but rather than getting bogged down with the analogy, do we agree that performance per watt is what matters? It doesn't matter whether you need 2 or 2.43 of them to match an RTX 3090, if it has better performance per watt, it's better.
> Right, but rather than getting bogged down with the analogy, do we agree that performance per watt is what matters?

No, I am not in agreement with you, the RTX 3090 is clearly better at being a GPU.

> clearly better

better is subjective, it depends on your needs.

sometimes performance per watt is more important especially when you're mobile or trying to be conservative w/ electricity.

> sometimes performance per watt is more important especially when you're mobile or trying to be conservative w/ electricity.

There is an obvious implicit context when you're comparing performance to an RTX 3090, and it is not mobility or your electric bill.

There may be only one implicit context for you, which is why I said "better" is subjective.

Personally the M1 Ultra would be better imo as a desktop GPU than RTX 3090 in certain contexts. Putting it in a van, traveling with it, etc.

I'll probably wait until the next go around of them, but I'm loving nearing desktop performance w/ reduced loads.

The RTX series has lower power variants. When you compare against the 3090 you are establishing a context with power consumption as a low priority.

Considering the 3090 had over double the performance, the lower power parts may well be both faster and more power efficient. You'd have to do the comparison to know, if that's what you care more about.

> 3090 had over double the performance

The FPS was closer than double. The flawed benchmark the 3090 had double.

I'm not sure how the lower power RTX variants compare, maybe that's a closer comparison, has there been a review against those?

I would ask if the RTX 3090 is competitive in some of the specialized things the Mac chip is made to do: there's a hell of a lot of dedicated video processing stuff in there that seems to exist to serve Final Cut Pro, not gaming. Are we comparing apples and oranges, in the sense that video editing at 4k, 5k and beyond might call upon a different set of skills than gaming benchmarks? How much would it matter if this translated into rather proprietary things like ability to pump impossible amounts of ProRes video compression on the fly and scrub ridiculously giant frame sizes? Are there benchmarks along those lines?
> do we agree that performance per watt is what matters?

No? Certainly not on desktop computers.

Performance per watt is very important for devices that need to run on battery and for cloud compute where you're running thousands of them and saving on electricity/cooling would be significant.

But it's almost completely unimportant for always-plugged-in-to-wall-socket desktop chips. Because even the power consumption of stuff like the 3090 is still pretty insignificant on your power bill compared to up front cost, and relative to the power consumption of all the other stuff in your house.

Remember even the 3090 consumes very little power when idle - it's only pulling the rated ~300w when you're maxing it out playing heavy games or rendering or whatever.

It doesn't go as fast as a 3090 even with two. It does go about twice as fast as an M1 Max.
First graph with geekbench scores.

RTX3090: 215,034

M1 Ultra: 102,156

The GB Compute test is widely viewed as worthless for the m1 Ultra chip because it’s too fast for the chip to ramp up. It’s even too short for the m1 Max.
Geekbrench has already been debunked a long time ago by Anandtech as not sustaining the full load enough to show the real pref.

The CPU and GPU tests finishes too fast for the system to ramp up to the full power load.

That's not to say that M1 Ultra is equal or better than 3090, just that Geekbench isn't the right test for this.

You can see more detailed analysis here: https://www.youtube.com/watch?v=pJ7WN3yome4

Is that an indication that the M1 has latency issues vis-a-vis power delivery, then?
That’s nice to know, but for me the M1 Ultra performance is not very relevant. Apple has a history of introducing proprietary architectures, not-quite-compatibles interfaces and non-standard software.

MacOS has nice UI? Great, I will use it. Anything computationally intensive? - Why bother? I would use only Linux on the back end. It’s very easy to couple mid-range Apple product with high-end Linux workstation at your desk. I don’t need to run compute-intensive Deep Learning load while I am at the coffee shop.

>I don’t need to run compute-intensive Deep Learning load while I am at the coffee shop.

Well they're putting it in a desktop and claiming desktop performance...

If Apple is going to put up graphs saying they beat i9 and 3090RTX machines, it's worth investigating even if I plan to put Linux on it.

In this instance it seems like the reality doesn't match the hype as well as in the laptop space, but if it had I would surly consider the option.

No. You have two electric cars both going at 80 mph, with twice the weight. Strap them together aaaaaand.... They're still two electric cars going together at 80mph. But if you're counting wheel rotations, well now you have 8 spinning wheels. Top speed will still not match the Lamborghini.
Weight barely matters for top speed. Air drag is the real factor.
I am quite happy with my Macbook Pro M1 Max, which remains virtually ice cold even running heavy compute (I am still yet to hear the fans spin up) and having a battery life that can accomodate easily 12+ hours of real work. Any Windows laptop with a 3090 inside it, will be a hot and loud brick in comparison. Granted I dont play video games, and my ML compute is run in the cloud it fits my needs nicely. I would argue in terms of sheer generalised productivity nothing else comes close.
Same here. Great computer. The only thing I am missing is a bit more reliable support for waking up external monitors. Between my now two m1/m1 max macs and 6 screens I use, one (an Asus 2k display which is slow to wake up from sleep) often requires unplugging to wake up. That is not a m1 issue - its been like that with macos since... forever, but it's irritating.
I use a 4 monitor setup for my workstation. I switched to a desktop computer in part to not have to deal with this exact issue with a MacBook.
What is your monitor layout?
I have those 6 screens plugged to two different macs, so just 3 on each. Big screen in the center, and two in portrait mode on the sides. One uses 43" 4k for the center screen, the other uses a 34" ultrawide.

The m1 max drives its displays directly, the m1 via a starlink tripple 4k displaylink hub.

The problems, in my case, are specific to monitors that take a good few seconds to come back from standby. Macos seems to be impatient and considers them dead. I am down to just 1 screen with this problem, and will replace it at some point.

One big thing holding me back from jumping on one is macOS. I’m sure it’s ok but I’ve been using Linux for ~25 years that’s a lot of muscle memory to lose. I really wish apple supported Linux better.
Hope Asahi Linux will get mature and be daily driver usable in the near future.
The only way I was able to get mine to spin the fans (at seemingly full speed!) was to build the Telegram Android app in "afat" variant. The NDK (which is still x86-only, shame on you Google) fully loads all cores for an extended period of time. The fans start several minutes in.
According to Max Tech analysis here, https://www.youtube.com/watch?v=pJ7WN3yome4, the GPU seems to max out at 60-70w at the moment for full load, even if the heat is well-managed. If Apple let it go up to 100-120w, we could see much more performance out of the GPU but for now, something is not set up correctly on macOS.

So, we may have to wait to see what Apple says or if they'll unlock the full performance in future software updates. They did do this in the past with M1 hardware a few times.

Same result here from another channel where it appears GPU isn't at full power atm: https://www.youtube.com/watch?v=0CUoHwMtRsE&t=1172s

The strategy of creating a large die with lots of execution units, then running the chip at a lower clock speed for power efficiency has been Apple's way of doing things for a while now.

>Apple has built a wide enough GPU that they can keep clockspeeds nice and low on the voltage/frequency curve, which keeps overall power consumption down. The RTX 3090, by contrast, is designed to chase performance with no regard to power consumption, allowing NVIDIA to get great performance out of it, but only by riding high on the voltage frequency curve.

https://www.anandtech.com/show/17306/apple-announces-m1-ultr...

This strategy is something that Anandtech's been calling out since the iPhone 5s chip.

>Brian and I have long been hinting at the sort of ridiculous frequency/voltage combinations mobile SoC vendors have been shipping at for nothing more than marketing purposes. I remember ARM telling me the ideal target for a Cortex A15 core in a smartphone was 1.2GHz. Samsung’s Exynos 5410 stuck four Cortex A15s in a phone with a max clock of 1.6GHz. The 5420 increases that to 1.7GHz. The problem with frequency scaling alone is that it typically comes at the price of higher voltage. There’s a quadratic relationship between voltage and power consumption, so it’s quite possibly one of the worst ways to get more performance.

https://www.anandtech.com/show/7335/the-iphone-5s-review/2

> The strategy of creating a large die with lots of execution units, then running the chip at a lower clock speed for power efficiency has been Apple's way of doing things for a while now.

> This strategy is something that Anandtech's been calling out since the iPhone 5s chip.

Not sure that applies to M1 Ultra that's clearly marketed as a desktop SoC, not a mobile device or laptop SoC. Optimizing for energy efficiency or battery life is not the same as optimizing for performance first, which is what M1 Ultra is designed for. Not to mention, there's a reason Windows and Linux have multiple power profiles that changes how schedulers and power loads work. macOS has "high power mode" for m1 on laptops and yet strangely, it is not even available on the Mac Studio.

Keep in mind that Apple showed a graph that clearly shows the GPU was at 100-110w. Why do that if they won't run it at that wattage or even talk about 3090 in the first place? Why ruin their reputation over a silly little thing? Everyone on the planet will easily debunk that.

Also, why even bother adding a high-quality cooling system that the Mac Studio clearly don't need since both CPU/GPU are going to be capped at lower power wattage?

We'll find out eventually one way or another.

> Not sure that applies to M1 Ultra that's clearly marketed as a desktop SoC, not a mobile device or laptop SoC.

The M1 Ultra is using the same CPU cores and GPU cores as an iPhone, just more of them.

It's long been their strategy across the board. Throw silicon die area at tons of execution units and run the chip at a lower clock speed for power efficiency.

For example, the 2012 A5X iPad chip had about the same die area as 4 core Ivy Bridge, which was huge for a mobile device SOC.

https://www.anandtech.com/show/6330/the-iphone-5-review/4

Since they are selling the whole widget, they aren't as dependent on minimizing die area to maximize their profit margin.

> The M1 Ultra is using the same CPU cores and GPU cores as an iPhone, just more of them.

Not only that, but it's running them at basically the same clock speeds as the rest of the M1 family, and even as the iPhone. This suggests that they're running at not far above a best efficiency point, rather than way past the elbow of the voltage curve as is traditional for desktop chips.

I would have thought this approach would cause issues for leakage power? Better to run fast then sleep and power gate to cut leakage, especially at smaller geometries.

Or do you think they are mostly using HVt cells?

Doesn't power leakage get much, much worse as temperature increases?
Yes it does, but that just means you want to use as little power as possible (which is presumably already the case).

That effect is actually so bad that I have previously experienced thermal runaway due to it (more power => higher temperature => more power => …)

> If Apple let it go up to 100-120w

GPUs and CPUs are not simply "pump more power in it to go faster hurr hurr". It is extremely likely that the M1's maximum performance is attained already. Otherwise, the M1 ultra would have pumped a little bit more wattage and gotten better single core perfs, but guess what, it doesn't.

> GPUs and CPUs are not simply "pump more power in it to go faster hurr hurr".

I agree, they're not a simple "throw more power and it'll go faster" problem. However, that doesn't mean they do not go faster if you increase clock speed and give it a little more power.

After all, overclocking would be utterly pointless over the past two decades and Intel/AMD wouldn't benefit from the so-called turbo boost technology. (I know M1 doesn't have turbo boost).

Just to be clear, yes, there's a limit to everything of course. There's a balance where certain higher clocks would cause a bottleneck in the rest of the system since this is a SoC.

In this case, I used the 100-120w number because Apple used that number in their GPU graph showing the GPU running at ~105w, why bother showing that if it can't accomplish it? Here's the graph: https://images.anandtech.com/doci/17306/Apple-M1-Ultra-gpu-p...

Note that Apple shows 60w for their CPU graph (https://images.anandtech.com/doci/17306/Apple-M1-Ultra-cpu-p...), which did actually match up and does show the double CPU pref that Apple stated.

I didn't pull that number out of nowhere. If Apple used 60w in that graph, then I wouldn't be here.

> Otherwise, the M1 ultra would have pumped a little bit more wattage and gotten better single core perfs, but guess what, it doesn't.

That's because of two reasons:

1. There is only so much data wecan "process" within the same core, more power does not change the data itself, we can only increase the clock speed to finish it faster or widen the amount of data that can fit in the same core. Also of note that Intel Turbo Boost does actually help with single-core thread pref by boosting the single core speed beyond the base line. 2. M1 max clock speed is set to 3.2Ghz (single core), it can't go faster than this (set by Apple). Throwing more wattage here wouldn't change anything but throwing more power to allow all 16 P cores to hit 3.2 does improve performance as long as it isn't overheating. I don't think M1 Ultra does hit 3.2 on all 16 cores (it might have hit 60w max first; I might be wrong but I saw mostly just 3.0ghz in Max video but I have to go back to review it).

Again, this is not about single-core performance, this is about GPU performance, which is extremely parallelizable and more comparable to the multi-core performance instead.

Apple has historically seemingly been allergic to good thermal design. I would not be surprised in the least if they were leaving a lot of performance on the table because they'd rather do that than design proper cooling, despite how silly that sounds.

(Although with the m1 line it actually makes a bit of sense for once - it is useful to the end user to set things up so that fans /never spin up/ and the laptop never gets hot to the touch. Whereas with their previous intel models they had terible cooling and still had all of those problems, while not actually achieving a size win over a lot of competitors "thin and light" models that actually had competent thermal design)

You know what, Mercedes uses Renault engines in some of its cars that are intended for luxury daily use.

Better != Faster or Better != More powerful

Better means closer to fulfil the goals and often the goals are inversely proportional(i.e. cheaper, faster, cooler are the goals but faster meaning less cheaper and hotter).

Apple might be guilty of misrepresentation of raw computational power but with M1 the experience of using computers has become significantly much better.

Actually better depends on the criteria. A Volkswagen Beetle can be better than any of the listed cars if you consider the type of road an easy of repair.
Mercedes only uses Renault engines in its absolute bottom of the barrel products.

Mercedes, unlike BMW with Mini and Audi with the VW parts bin has to outsource the low end stuff.

> without mentioning the fact that a Lambo can still go twice as fast

To be picky about this analogy, top speed in a car is an attribute that bears little on everyday utility. In fact, past the 110km/h here in Australia for instance, the only place you can enjoy the extra speed in on a track. %99.999+ of people won't be able to take advantage of anything for entire life of their vehicle.

On the contrary, instant acceleration is something every driver takes advantage of numerous times per day, when changing lanes, correcting for others mistakes, etc. Fuel cost savings and low maintenance saves every driver money. These are the attributes to pay attention to in a car in general, not the top speed.

Point is to pay attention to characteristics which are of utility towards the use case. Obviously, if you are getting a car to go as fast as you possible can on a track, you want a car with higher max speeds so there is that.

Without delidding both you can't really tell anything. It might very well be that 80% of the area of the ultra is just SDRAM.
SDRAM is not located on the chip die for either. The memory controller is on-die for the M1 though. My understanding is that making SDRAM is a pretty different process than making a CPU, so it's hard to do it on the same die.
This article is comparing package sizes, and DRAM is on package for the M1s.
The CPU is the same size as the thermal paste residue shown in the pictures. The remaining space is for the two RAM chips. The author should be embarrassed.
You know, there's a few articles out on this size difference subject; if they can make my CPU 10% faster by doubling the physical size -- all other things being equal I'd take that.
Cost increases super-linearly with size. One reason for this is defects: if a single defect ruins a whole chip, then for a constant number of defects per square inch, you'll get more usable square inches of silicon when you have small chips than big ones. Of course you can build chips that can tolerate a few defects, but the principle holds.

This is also why high quality TVs are harder to manufacture than high quality phone displays. You have a lot more waste when you need to throw out/recycle a TV screen compared to a phone screen. And both are considered bad when they have just one bad pixel.

>for a constant number of defects per square inch

Is this assumption true?

Its more the geometry of the process than the rate of failure. The post is just saying, "if the rate were constant". Basically, throw a dart at a wafer. Wherever the dart hits, the whole circuit/chip containing that point is now worthless. Assuming you threw the same number of darts (failures) at a board with a smaller chip, and a board with a large chip, the larger process wafer loses more total silicon (as a percentage of usable area).

With smaller chips, you have a smaller "grid" for your dart to land on. So the total number of failures (darts) being the same, you still end up with less usable silicon, since the bigger grid means you throw away a lot more surface area with a failure.

Take a look at this picture of a failure map, if you would like some visuals: https://ars.els-cdn.com/content/image/1-s2.0-S09521976120008...

That image kind of looks like cosmic ray trails in a cloud chamber, I wonder if some of the defects are related.
The point is that the amount of silicon that is wasted when there is a defect is amplified more with larger chips. That assumption was more for ease of explanation, but perhaps I could have explained better.
> a single defect ruins the whole chip

no. intel used to make extra cores for their 128 core cpus to account for the defects, and it was not rare to receive a cpu with more than 128 cores because it was a good one.

See the next sentence: "Of course you can build chips that can tolerate a few defects, but the principle holds."
Isn't this why AMD is going with chiplets design? No reason they can't manufacture even larger processor then, right?
One of the reasons, yes. Another benefit of chiplets is mixing and matching chips made on different processes or from different manufacturers.

AMD uses an IO die manufactured on an older process at another manufacturer (14 or 16nm Global foundries) than their core chiplets (7nm TSMC). I think they even used the same IO die across multiple generations of EPYC/Ryzen, but I'm not sure.

Would you pay 2-3x the price? That’s the tradeoff…
Given that Apple devices already have 2-3x premium, as long as Apple absorbs the extra cost, people would be fine with it.

This is also why the approach is an "Apple-only" one.

The whole point of the M1 debate is that they aren’t 2-3x the price though.
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> Given that Apple devices already have 2-3x premium

You're suggesting Apple devices cost between two and three times as much as the competition? I'd like to see that competition, so please show us those $280 Mac Mini and iPhone 13 Mini killers. Or, conversely, show us a superior device for the same price. Remember to match point for point all features of whatever Apple device you somehow believe costs 2-3x as much as it's third party clone.

M1 Ultra has a 3x larger heat-spreader than Ryzen. That’s the entire package and not the silicon chip itself.

Also, let’s not forget that this heat-spreader includes the RAM under it.

Here’s the funny bit: the silicon die for M1 Ultra is actually more than 4x bigger than Ryzen 5000 series. M1 Max was 432 mm2; implying 864 mm2 of silicon. Ryzen 5000 has a 84 mm2 CCD and 124 mm2 IO die.

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I’m guessing the price scales at least linearly with the size. I do hope the new trend isn’t giant chips because the price and availability would be horrible
It's generally superlinear due to yield effects - this is a bit oversimplified, but in particular, with lithography defects being more or less randomly placed throughout the wafer, a defect in a 100mm2 die impacts a far smaller percentage of the dies in the wafer than a defect in an 800mm2 die. Assuming a constant defect rate per wafer, you'll end up with drastically less usable wafer area with large dies than with small ones.

This was a major reason that AMD was able to price Ryzen so aggressively even at the high end - a high-end CPU is just made of more of the same small dies used in low-end CPUs, albeit requiring a better bin, instead of having to make a much larger single die.

The constant defect rate isn't typically a correct assumption across different products (e.g. different CPU or GPU dies) - different feature designs will have differing defect rates. Maybe Apple was able to design the M1 Ultra's features so that defect rate is very very low, though - I don't really know much about that silicon.

probably this is why they decide to do it as last m1 product, in genera the more you use a process -> less error in the production process happens.
This is probably M1 Ultra is designed to be two M1 Max glued together, more or less.
The M1 Ultra would be at or over the reticle limit as a single die, depending on how much area could be saved by removing the inter-die transceivers.
I don't think that's a deal breaker if you're willing to lay thick interconnects, treating the connection much like you'd treat something like EMIB.

After all, Cerebras made a functional wafer sized chip.

> After all, Cerebras made a functional wafer sized chip.

https://cerebras.net/

Yes, but the Cerebras wafer-chip is a repeating pattern of logic, memory, and interconnect tiles. Each pattern is well under the reticle limit of the process node they're using.

And how many Cerebras wafers have shipped? I would imagine that they can afford to spend more engineering effort in the late manufacturing phase, fusing off bad bits, maybe salvaging some other bits... but enabling such late-stage functional-unit binning requires a larger mesh topography.

Apple is using a design that's at the limit of economic feasibility at the mass-market sales volume they can support. They can amortize the engineering expense down among the single most popular retail item on the planet.

Cerebras is an engineering marvel, but I wouldn't call it a mass-market item.

The Mac Studio more closely resembles high-end IBM POWER mainframe modules.

Stunning that you can just go out and buy one. And you don't need a data center to feed it.

https://www.anandtech.com/show/16626/cerebras-unveils-wafer-...

https://cerebras.net/

But you'd also keep each half of the M1 ultra under the limit.

I'm not saying it's a good idea, because they'd have done it if it was. They clearly know what they're doing.

I'm just saying that it's not an absolute blocker for a design you'd otherwise be connecting over something like EMIB anyway.

... three days later ...

Oh, I see: you are wondering why Apple M1 Ultra, as two chips linked by EMIB, couldn't just be the two chips adjacent on the wafer.

See the difference? Apple knows what their yields are; if they could be sure to get two matched SoC M1 Max chips right next to one another on the wafer, they could punch that pair out and bypass the whole EMIB thing.

I don't know enough about testing and dicing 100-billion-transistor chips to know how expensive that would be.

Is it actually 2 different pieces of silicon though? I thought they were 2xM1 Max as a single silicon. Which wouldn't help with defect rates
It is two separate dice, with an EMIB-style interconnect.
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That makes a lot of sense. The Max is still pretty fucking big, but two of those is a lot more manageable than a single monolothic die double the size
I just listened to the latest atp.fm podcast. I think John said that it actually is two adjacent M1 max dies. The Ultra can’t be made from two random working die. They have to physically be adjacent on the wafer.

I don’t know if that means it’s physically one due though.

Usually dies aren't mirrored on the wafer so I'm calling citation needed on this one.
Not sure if the counts. I know it’s a patent and it could be anything. But it talks about two adjacent dies being used if they’re good or being split if there is a defect.

https://patents.google.com/patent/US20210217702A1/en?oq=2021...

Thanks for the link. I'm not a lithography expert, but this looks like a Cerebras-style approach at a smaller scale. It might be cheaper than the EMIB/InFo approach since there's no interposer with the associated alignment and thickness issues. In the keynote Apple explicitly said they're using a silicon interposer, which doesn't sound like this patent.
Apple has both a 48 core & 64 core GPU variant of the M1 Ultra. Since the GPU is the largest single element of the M1 Max / Ultra, that's how they are handling yields. And it's then +$1000 for the 64 core variant over the 48 core, suggesting probably "normal" TSMC yields and then a very healthy profit margin. Apple does have the luxury of just charging whatever they want for this SoC since they are a market unto themselves. So even if yields are bad, they can just pass that cost along to the consumer.

Not entirely unlike what Intel used to do with Xeons before AMD re-entered the picture and what Nvidia kinda does with the likes of the A100.

I think the Ryzen 6000 laptop chips are a better comparison. They are also monolithic, contain a powerful GPU, and are manufactured on a more similar node. Ryzen 6000 has a die size of 210mm².
M1 Pro is 251.3 mm² with a ~5 TFLOPS GPU and Rembrandt is 210 mm² for 3.4 TFLOPS so the comparison checks out.
It's a slightly better comparison, however Ryzen 6000 is on N6 (which is an optimized N7 process), whereas M1 Max is on N5. N5 is considerably denser than N6.

AMD's next round of APUs on 5 nm will offer a better die area comparison.

I remember reading that at 5nm, electron tunnelling through transistor gates would be a major problem. What happened to that?
I think the do funky stuff with the 3D or 2.5D geometry of the gate so that the surface area (between transistors) is larger for a smaller footprint.

Someone correct me if I’m wrong!

Yes, that tech is called FinFET and it has been in use for many years. The new hot thing is GAAFET (Gate-all-around FET).
5nm doesn’t mean anything is actually 5nm. It’s the “5nm node”

Marketing dept has trumped physics.

That would be the case if 5nm didn't refer to a random feature of a reference planar transistor that is only used to chronologically name the process according to its mathematically equivalent density..
Why not spread the processor across the whole Macbook motherboard, wouldn't this bring huge cooling benefits with no major downsides?
The downside would be latency increase / speed reduction.
Speed of light is something like one foot per nanosecond. So at 2GHz you go 6" per clock, assuming you can actually go the speed of light which, in a wire, you can't.
The whole point of going to smaller nm process is to bring things closer, so it takes less time to move information.
The shorter signals have to travel, the less time and power it takes to do so.
Yep, It’s a poor comparison, the Mac chip has up to 128 gig of RAM under there, and other stuff like SSD controller, etc..

It is kind of awesome to look at though.

I wonder about the size comparison between the M1 Ultra and surface area of the equivalent 'Ryzen CPU + Radeon GPU + RAM :D'
A 5950X is 285mm² in total (and made with TSMC 7nm). An RTX3080 is 682mm² (and made with Samsung 8nm). A 16GB DDR5 die seems to be about 75mm².

RAM aside which is Apple's actual performance differentiator, all of these eat the M1 Ultra alive in their respective categories.

Going a bit further, since the chips are all on different processes (Apple on TSMC N5, AMD on TSMC N7, and Nvidia on Samsung 8N), it might also be worth looking at transistor counts. The M1 Ultra has 114B transistors, a 5950X has 19.2B transistors, and a 3080/3090 (GA102) has 28.3B transistors.

(at 864mm2 (2 x 432mm2 M1 Max's), that's a density of ~130MTr/mm2, which is in the ballpark for TSMC's max density for N5 (est. 170MTr/mm2) - N7 max density for reference is ~90MTr/mm2)

But would you even buy the equivalent when the gpu and ram were "hard-coded"?
yeah, because it does not operate as a space heater. I can buy one of those for like $100, and that's a high end model.
I saw this earlier but since I can only see the main image and reading didn't net an answer - what, exactly are they measuring? I am not expert but to my understand part of ryzen success is high yields due to small size. Having a thing 3x its size, while impressive, is not super surprising.

Soon it will be 6x, then more. Zen 5 small cores are supposed to be just zen 4 cores iirc.

The technically interesting bit about the Ultra's GPU is that it makes multiple GPU dies look like one physical GPU to software:

>if you could somehow link up multiple GPUs with a ridiculous amount die-to-die bandwidth – enough to replicate their internal bandwidth – then you might just be able to use them together in a single task. This has made combining multiple GPUs in a transparent fashion something of a holy grail of multi-GPU design. It’s a problem that multiple companies have been working on for over a decade, and it would seem that Apple is charting new ground by being the first company to pull it off.

https://www.anandtech.com/show/17306/apple-announces-m1-ultr...

You've posted this maybe 3 times in the past week, all on articles that have nothing to do with the multi-die nature of the M1 Ultra. What is the salient information here that we couldn't ascertain from watching Apple's keynote or scrolling through their landing page?
This is literally a point made in this article too.

How is it not relevant in this thread?

So why not quote this article instead of linking and quoting a different article?
Isn't this a terrible choice of websites if you are upset by discussion that calls out a genuinely new technological feat in the computer industry?
It's not new, AMD has been doing this for a while with their Infinity Fabric technology (and before that, technologies like SLI and Crossfire achieved the same thing on a software level), and you've posted about it several times already. It's also not much of a "feat", since it was done by a company with 200 billion dollars in liquid cash that could probably cure cancer if they wanted to. Not only is it completely uninteresting from a technical standpoint, it's also something you've repeatedly posted on threads that outline the downsides of doing this (like yesterday's benchmark results, showing how strapping 2 M1 Max GPUs together doesn't yield twice as much compute power).

Frankly, it's annoying, and pretty far from intellectually stimulating. What is there to discuss anyways? Do we all need to pat the world's largest tech conglomerate on the back for doing the same thing as other companies did 6+ years ago, with worse performance results and misleading marketing material to boot?

>It's not new, AMD has been doing this for a while with their Infinity Fabric technology (and before that, technologies like SLI and Crossfire achieved the same thing on a software level)

None of those technologies make multiple GPU dies look like a single physical GPU to software.

As covered by the Anandtech quote you dislike so much:

> This has made combining multiple GPUs in a transparent fashion something of a holy grail of multi-GPU design. It’s a problem that multiple companies have been working on for over a decade, and it would seem that Apple is charting new ground by being the first company to pull it off.

However, that article does go into additional detail.

>Unlike multi-die/multi-chip CPU configurations, which have been commonplace in workstations for decades, multi-die GPU configurations are a far different beast. The amount of internal bandwidth GPUs consume, which for high-end parts is well over 1TB/second, has always made linking them up technologically prohibitive. As a result, in a traditional multi-GPU system (such as the Mac Pro), each GPU is presented as a separate device to the system, and it’s up to software vendors to find innovative ways to use them together. In practice, this has meant having multiple GPUs work on different tasks, as the lack of bandwidth meant they can’t effectively work together on a single graphics task.

https://www.anandtech.com/show/17306/apple-announces-m1-ultr...

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He is just enthusiastic about some specific point, and wants to discuss it with HN readers. No harm in it.
Isn't this an OS feature?
No, I think the OS sees it as a single GPU.
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> The drives use a proprietary form-factor, which is logical as the SSD controller resides in the SoC, and the drives themselves do not need to carry one

No, it's not logical, they still could have used a common form factor like M.2.

What, make a socket matching the M.2, that M.2s would be incompatible with?
Intel actually does just that with wifi cards (CNVio/2 cards only work with specific chipsets and don't use PCIe/USB, while using the same keying as normal wifi cards).
An M.2 2230 slot should be able to take Wi-Fi or NVMe since they're both PCIe devices. In practice there aren't many 2230 SSDs.
CNVi isn't PCIe; non-CNVi platforms can't take CNVi Wi-Fi cards.

> CNVi or CNVio ("Connectivity Integration", Intel Integrated Connectivity I/O interface) is a proprietary connectivity interface by Intel for Wi-Fi and Bluetooth radios to lower costs and simplify their wireless modules. In CNVi, the network adapter's large and usually expensive functional blocks (MAC components, memory, processor and associated logic/firmware) are moved inside the CPU and chipset (Platform Controller Hub). Only the signal processor, analog and Radio frequency (RF) functions are left on an external upgradeable CRF (Companion RF) module which, as of 2019 comes in M.2 form factor (M.2 2230 and 1216 Soldered Down). Therefore, CNVi requires chipset and Intel CPU support. Otherwise the Wi-Fi + Bluetooth module has to be the traditional M.2 PCIe form factor.

https://en.wikipedia.org/wiki/CNVi

True; I was thinking of normal Wi-Fi cards.
Right, but that would hardly serve any practical purpose, as one still couldn't plug an off the shelf m.2 device and expect it to work. So - why constrain yourself with someone elses connector design if if adds no value?
That would make 0 sense. It would be confusing even since no M.2 device would work in that slot.
Besides how malicious it would be to use an M.2 physical connector for a non-M.2-compatible protocol, the pin count on the Apple connector is much higher for a reason. Adding a chip on to the SSD to mux between the different flash signals and retransmit them over a reduced number of high speed transceiver lanes would be cost-wise most of the way to putting a traditional PCIe controller on the SSD, without the benefits.
I am very curious about the production yields of these monsters. Things can go wrong at the cpu, the gpu, the memory etc and any of these reasons will lead a chip to the trash bin.
The M1 Ultra is essentially two M1 Max joined together. I suspect most of the things which can go wrong are at the M1 Max level. I'm sure a certain percentage where fusing two dies together kills one or both dies, but I suspect that's probably a manageable percentage.
in general the lower yield ones ended up being the lesser model such as M1 Pro using the same die
On the latest episode of the Accidental Tech Podcast they were discussing a patent related to this fancy interconnect stuff, and it sounds like not only do they need two fully functioning M1 Max's, but they also need to be adjacent on the wafer. Although I guess at least they can still use the non-defective M1 Max in any pair.
That would be an interesting approach: don't know if it's what they're doing, but if they're like 'make M1 Ultras predominantly, but then if they break you're making M1 Max with an attached bit that has to be trimmed off', that's pretty ingenious.
I think I've seen a picture of a decapped M1 Max and it had this extra part on the side that never appeared in Apple renders. It was back then when this speculation of it having multiprocessor interconnect started. It was then also confirmed by Asahi Linux people from the software side of things.

So no, they don't even bother to trim it off.

This is the reason there are lower-end models of all M1 chips with some CPU and GPU cores disabled. And the M1 Ultra is just two M1 Max glued together.
> Things can go wrong at [..] the memory etc

The memory isn't on die. It's just regular lpddr5 but on package. So that's not a yield concern.

Does the M1 Ultra use a chiplet design like the Ryzen series? Otherwise the yields have to be awful.
The ultra uses two identical dice in a single package, with an EMIB-style interconnect. This is fewer, larger, and more uniform dice than the Ryzen approach, but still not monolithic.
I'd rather see the delidded version as this is comparing a CPU, to CPU+RAM and without delidding we don't know how much space is taken by the ram dies.

As it is, this is a kind of clickbaity article

Isn't the M1 Ultra more comparable to a SoC than the discreet cpu Ryzen chips are?
Ryzen chips are more of less, SoC.
AMD internally refers to the finished product as the SoC, and the chipset (no longer a northbridge, the NB is on die) as a socket extender (a term also used by most SoC vendors) in internal documentation.

Also, arguably, the IO Die is the SoC, the chiplets are external to the SoC even though they all live on the same interposer.

Fair. I think we can probably consider them to be less of a SoC than the M1 Ultra though - Ryzens do have a lot in them, but not all the system's RAM for example.

(which is a good thing. all-in-one for specialized stuff is fine, but I don't want it to become the norm - upgrading one component is cheaper than upgrading multiple, and tends to support longer hardware cycles)

I didn’t think Ryzen included on package ram?
Looks like a great platform but you can't have it as a daily driver if you use anything that depends on amd64 from what I have been able to find out.
I always heard that the reason we don’t just make chips bigger is that it increases the distance the electricity has to travel which translates to more latency. But somehow rhe M1 Ultra is able to get away with being huge with out this being a problem.

I wonder if we will start seeing more physically large chips in the future because of this?

This die includes RAM. On a traditional motherboard the ram is further away from the cpu than in here. Same story for GPU.
So not only is AMD Ryzen smaller and less densely packed, with 112 billion fewer transistors, it doesn't have any RAM on it? What else is the M1 Ultra bigger than? Are we gonna need a bigger boat?