A18 Pro … your thoughts?

[tomO2013]

Interested to hear your guys thoughts (based on the extremely limited information) that Apple shared today ?

If benchmarks back up (which I have no doubt they will) Apples numbers (which in recent years have tended to sandbag just how good improvements have been), then this is a nice step up.

I’m particularly interested to learn how they got a 2X ray tracing performance improvement - new GPU architecture? They claim a bandwidth improvment of 20% but that wouldn’t alone account for it.

The other area that I’m interested to learn more about is the direct programmable ML accelerators…

The next M4 Pro/Max/Bodacious chips could be shaping up to be beastly.

 

[Altaic]

17% memory throughput improvement correlates to LPDDR5 6400 -> LPDDR5X 7500 with 60 GB/s. Same memory as the M4.

The direct programmable ML accelerators sound really interesting. I believe it was mentioned on the CPU slide (as opposed to the NPU slide), which makes me think AMX got a substantial redesign.

 

[Jimmyjames]

I guess much of the interest for me has lessened given the M4 iPad revealed much already. The more technical things will need to wait for M4 Macs. I do agree the 2x ray tracing is curious. I would assume that would carry over to the M4 Macs given the A17 Pro/M3 macs share an architecture and the A18 Pro/M4 do as well.

 

[tomO2013]

That’s what stood out most to me too from the CPU slide … well that and the ray tracing improvements.
The direct programmable ML accelerators sounds really interesting - this is something that many developers have been asking Apple for. I wonder if this will only be exposed through their accelerate framework?

I was a little surprised that they didn’t improve the neural engine more given their push for on-device apple intelligence, but touting out and out specs has never really been Apples modus operandei for selling it’s products.

 

[mr_roboto]

The direct programmable ML accelerators sound really interesting. I believe it was mentioned on the CPU slide (as opposed to the NPU slide), which makes me think AMX got a substantial redesign.

I'm sure this is just A18(Pro) getting the same CPU cores as M4 (or perhaps something slightly newer?), and thus gaining support for SME, Arm's Scalable Matrix Extension.

The direct programmable ML accelerators sounds really interesting - this is something that many developers have been asking Apple for. I wonder if this will only be exposed through their accelerate framework?

It's fully public. Basically Apple seems to have pushed on Arm to adopt and standardize AMX (Apple's private matrix math ISA extension) so they wouldn't have to keep it Accelerate-only any more. That's how we got SME.

 

[Altaic]

Since the A18 Pro got the direct programmable accelerators, I wonder if the M4 did as well? They certainly didn’t mention that with the iPad Pro release, and I haven’t noticed anything in the developer/api docs thus far.

Edit: @mr_roboto so you think the direct programmable ML accelerators is just SME? That’s kind of an odd way to describe SME. I guess I’ll go back and rewatch that part.

Edit 2: rewatched it (at 1:21:40 in the YouTube video), and he describes it as “next generation ML accelerators” that are “now directly programmable.” So yeah, that does sound like SME. Oh well.

 

[dada_dave]

I guess much of the interest for me has lessened given the M4 iPad revealed much already. The more technical things will need to wait for M4 Macs. I do agree the 2x ray tracing is curious. I would assume that would carry over to the M4 Macs given the A17 Pro/M3 macs share an architecture and the A18 Pro/M4 do as well.

Yeah I will add my voice to this here and elsewhere, are the ray tracing cores the same in the M4 and A18? They never mentioned anything on the M4 and I don't remember any massive ray tracing benchmark swings?

 

[leman]

I’m particularly interested to learn how they got a 2X ray tracing performance improvement - new GPU architecture?

This sounds like a new thing. Second-gen RT cores? I don’t remember M4 being advertised in the same way, so we could have a new GPU iteration.

The other area that I’m interested to learn more about is the direct programmable ML accelerators…

That is most certainly SME, which we already have in M4.

 

[Jimmyjames]

Yeah I will add my voice to this here and elsewhere, are the ray tracing cores the same in the M4 and A18? They never mentioned anything on the M4 and I don't remember any massive ray tracing benchmark swings?

Yes it’s interesting. I agree nothing much was said about the M4 ray tracing. At the same time, I’m not sure what takes advantage of ray tracing on the iPad, at least not like something like Blender would.

I’ve seen some say that the base M4 wouldn’t have this improvement but the Pro/Max would. I’d be surprised since they don’t usually separate functionality like this.

 

[leman]

Yes it’s interesting. I agree nothing much was said about the M4 ray tracing. At the same time, I’m not sure what takes advantage of ray tracing on the iPad, at least not like something like Blender would.

The same argument could be made for RT cores on the iPhone

I’ve seen some say that the base M4 wouldn’t have this improvement but the Pro/Max would. I’d be surprised since they don’t usually separate functionality like this.

I think an argument could be made in favor of using new tech as it becomes available. Blender is a popular app with people who buy MBPs, and it would be great PR for Apple if the new Macs are 10-15% faster in production RT. In the end, there is no advantage in waiting until next year if the feature is ready, and they have to design the layout for these new chips anyway. Might as well add some updated stuff.

Or it could be that the faster RT is just an A18 Pro thing and won’t be included in the M4 family. Who knows.

 

[dada_dave]

This sounds like a new thing. Second-gen RT cores? I don’t remember M4 being advertised in the same way, so we could have a new GPU iteration.

Yes it’s interesting. I agree nothing much was said about the M4 ray tracing. At the same time, I’m not sure what takes advantage of ray tracing on the iPad, at least not like something like Blender would.

I’ve seen some say that the base M4 wouldn’t have this improvement but the Pro/Max would. I’d be surprised since they don’t usually separate functionality like this.

I've checked Solar Bay. Max Tech says the 9 core Solar Bay M4 was 58 FPS and Shrout says the 10-core M3 got 51 FPS. Unfortunately different core counts but assuming the 10 core M4 would get about 63 FPS that is substantially more than the 15% clocks alone would expect (24% improvement) and it's possible that while Solar Bay has RT, depending on how much RT affects performance, that 2x might not show up as substantially as it might? So it's possible these new RT cores are in the M4? But it's also possible that they are new. Doesn't really confirm one way or the other. We'll have to see what Apple says in October/November unless someone gets a more definitive answer first!

 

[Jimmyjames]

I've checked Solar Bay. Max Tech says the 9 core Solar Bay M4 was 58 FPS and Shrout says the 10-core M3 got 51 FPS. Unfortunately different core counts but assuming the 10 core M4 would get about 63 FPS that is substantially more than the 15% clocks alone would expect (24% improvement) and it's possible that while Solar Bay has RT, depending on how much RT affects performance, that 2x might not show up as substantially as it might? So it's possible these new RT cores are in the M4? But it's also possible that they are new. Doesn't really confirm one way or the other. We'll have to see what Apple says in October/November unless someone gets a more definitive answer first!

Solar Bay is quite light on RT iirc. Just reflections I think.

 

[leman]

I've checked Solar Bay. Max Tech says the 9 core Solar Bay M4 was 58 FPS and Shrout says the 10-core M3 got 51 FPS. Unfortunately different core counts but assuming the 10 core M4 would get about 63 FPS that is substantially more than the 15% clocks alone would expect (24% improvement) and it's possible that while Solar Bay has RT, depending on how much RT affects performance, that 2x might not show up as substantially as it might? So it's possible these new RT cores are in the M4? But it's also possible that they are new. Doesn't really confirm one way or the other. We'll have to see what Apple says in October/November unless someone gets a more definitive answer first!

There is also some difference in RAM bandwidth and cache size, right? These could add up to 25% even without better RT.

 

[Jimmyjames]

The same argument could be made for RT cores on the iPhone

For sure. I suppose I meant we may not see the results of the improved RT cores on any current iOS software. Perhaps it will be apparent when the M4 Mac arrive.

I think an argument could be made in favor of using new tech as it becomes available. Blender is a popular app with people who buy MBPs, and it would be great PR for Apple if the new Macs are 10-15% faster in production RT. In the end, there is no advantage in waiting until next year if the feature is ready, and they have to design the layout for these new chips anyway. Might as well add some updated stuff.

Or it could be that the faster RT is just an A18 Pro thing and won’t be included in the M4 family. Who knows.

It’s intriguing.

 

[dada_dave]

There is also some difference in RAM bandwidth and cache size, right? These could add up to 25% even without better RT.

Possible though it was rare to see it go as a high as 24% - I think in my GB 6 GPU post on this I didn't see any individual test go that high. But it's limited enough that it's just hard to tell, only 8% over expected. Without more ray tracing benchmarks it's just too hard to tell.

EDIT: wait I wrote that it was a 10% clock speed increase from M3 to M4: https://techboards.net/threads/may-7-“let-loose”-event-new-ipads.4607/page-19#post-160887 and most GB results improved by at most 15%.

If so then those are more likely new RT cores in the M4 as well. Damn do we know what the clock speed increase is?

Edit 2: 10% clock speed increase



Geekerwan didn't think there was anything remarkable about the M4 GPUs performance. He talked about Solar Bay briefly but didn't show M4 results! I'm strongly leaning towards these RT cores being in the base M4 and somehow he missed this?

 

[Jimmyjames]

Possible though it was rare to see it go as a high as 24% - I think in my GB 6 GPU post on this I didn't see any individual test go that high. But it's limited enough that it's just hard to tell, only 8% over expected. Without more ray tracing benchmarks it's just too hard to tell.

EDIT: wait I wrote that it was a 10% clock speed increase from M3 to M4: https://techboards.net/threads/may-7-“let-loose”-event-new-ipads.4607/page-19#post-160887 and most GB results improved by at most 15%.

If so then those are more likely new RT cores in the M4 as well. Damn do we know what the clock speed increase is?

Edit 2: 10% clock speed increase



Geekerwan didn't think there was anything remarkable about the M4 GPUs performance. He talked about Solar Bay briefly but didn't show M4 results! I'm strongly leaning towards these RT cores being in the base M4 and somehow he missed this?

I imagine it’s easy to miss due to a lack of software that takes advantage.

 

[dada_dave]

I imagine it’s easy to miss due to a lack of software that takes advantage.

Possible but Solar Bay having a substantially higher increase than raw clocks should've stood out and he talks about Solar Bay so ... just doesn't show M4 results.

The M3 over M2 increased Solar Bay performance by 1.58 with no clock speed increase. M4 increased performance by potentially 1.24 with a 10% clock increase, so about 1.12 over clocks. Apple has said HW accelerated ray tracing over software ray tracing is about 4-5x faster and the new RT cores are 2x faster than the old ones ... that doesn't quite work comparing 1.58 to 1.12 but still ... could be benchmark specific. So I'm far from 100% certain, but again it seems like these are new RT cores in the M4. Maybe.

 

[Jimmyjames]

I know some people don’t like Twitter, but this RT mystery reminded me of this Tweet by Sebastian Aaltonen:
From this tweet https://x.com/SebAaltonen/status/1806249232656957682

 

[leman]

I know some people don’t like Twitter, but this RT mystery reminded me of this Tweet by Sebastian Aaltonen:
From this tweet https://x.com/SebAaltonen/status/1806249232656957682
View attachment 31246

He is talking about dynamic caching feature on M3. It is particularly efficient when applied to complex RT shaders.

 

[Jimmyjames]

From the Apple event video today at 1:18:26
“Thanks specifically to new enhancements to the GPU architecture, hardware acceleration can perform ray tracing up to two times faster"