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Apple’s new M1 Pro and M1 Max processors

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Re: Apple’s new M1 Pro and M1 Max processors

#781
post #450

It's a bit concerning that the new chips have special purpose video codec hardware. I hope this trend doesn't continue, requiring laptops from different manufacturers to play different video formats or at least with a non-degraded quality.

Video encode and decode have been GPU and integrated GFX features for quite a long time now.

Well, they've been features of special ASICs that just happen to be on the GPU. Video decoding is not really suitable for CPUs (especially since H.264 or so) but it's even less suitable for GPGPU.

Re: Apple’s new M1 Pro and M1 Max processors

#782
post #750

Earlier quoted context omitted.

I know nothing about hardware, basically. Do Apple’s new GPU cores come close to the capabilities of discrete GPUs like what are used for gaming/scientific applications? Or are those cards a whole different thing ?

1. If you're a gamer, this seems comparable to a 3070 Laptop, which is comparable to a 3060 Desktop. 2. If you're a ML researcher you use CUDA (which only works on NVIDIA cards), they have basically a complete software lock unless you want to spend an undefined number of X hundreds of hours fixing and troubleshooting compatibility issues.

There has been an M1 fork of Tensorflow almost since the chip launched last year. I believe Apple did the leg work. It’s a hoop to jump through, yes, and no ones training big image models or transformers with this, but I imagine students or someone sandboxing a problem offline would benefit from the increased performance over CPU only.

https://blog.tensorflow.org/2020/11/accelerating-tensorflow-...

Re: Apple’s new M1 Pro and M1 Max processors

#783

It makes me sad that no one will never be able to build anything with those chips. I imagine there could me many, many innovative products built with these chips if Apple sold them and supported Linux (or even Windows).

They wouldn't have existed in this form then. Open chip market has very different needs, and SoCs are designed accordingly.

Re: Apple’s new M1 Pro and M1 Max processors

#784

Earlier quoted context omitted.

You'd expect HBM or GDDR6 to be used. But this is seemingly LPDDR5 that's being used. So its still quite unusual. Its like Apple decided to take commodity phone-RAM and just make many parallel channels of it... rather than using high-speed RAM to begin with. HBM is specifically designed to be soldered near a CPU/GPU as well. For them to be soldering commodity LPDDR6 is kinda weird to me. --------- We know it isn't HB…

HBM isn't just "soldered near", it's connected through a silicon interposer rather than a PCB. Also we know it's not HBM because the word "LPDDR5" was literally on the slides :) > just make many parallel channels of it isn't that just how LPDDR is in general? It has much narrower channels than DDR so you need much more of them?

> isn't that just how LPDDR is in general? It has much narrower channels than DDR so you need much more of them?

Well yeah. But 400GBps is equivalent to 16x DDR4 channels. Its an absurdly huge amount of bandwidth.

Re: Apple’s new M1 Pro and M1 Max processors

#785
post #322

Earlier quoted context omitted.

Really curious if the memory bandwidth is entirely available to the CPU if the GPU is idle. An nvidia RTX3090 has nearly 1TB/s bandwidth, so the GPU is clearly going to use as much of the 400GB/s as possible. Other unified architectures have multiple channels or synchronization to memory, such that no one part of the system can access the full bandwidth. But if the CPU can access all 400GB/s, that is an absolute game…

More memory bandwith = 10x faster than an i9 ? this makes no sense to me doesn't clock speed and cores determine the major part of the performance of a cpu ?

Yes and no. There are many variables to take into account. An example from the early days of the PPC architecture was their ability to pre-empt instructions. This gave performance boasts even in the absence of a higher clock speed. I can't speak specifically on the M1, but there are other things outside of clock speed and cores that determine speed.

Re: Apple’s new M1 Pro and M1 Max processors

#786

Earlier quoted context omitted.

USB-C 3.1 PD delivers up to 240watts.

That's with 2 connectors right? I have a Dell Precision 3760 and the one connector charging mode is limited to around 90W. With two connectors working in tandem (they snap together), it's 180W. The connectors never get remotely warm .. in fact under max charge rate they're consistently cool to touch, so I've always thought that it could probably be increased a little bit with no negative consequences.

Single connector, the 3.1 spec goes up to 5A at 48V. You need new cables with support for the higher voltages, but your "multiple plugs for more power" laptop is exactly the sort of device it's designed for.

It was announced earlier this year, so not in wide use yet. PDF warning: https://usb.org/sites/default/files/2021-05/USB%20PG%20USB%2...

Re: Apple’s new M1 Pro and M1 Max processors

#787
post #712
post #639

Earlier quoted context omitted.

this is mostly wrong. The real issue has always been memory bandwidth. the highest end consumer x86 CPU has about the same memory bandwidth as a dGPU from 10 years ago. The M1 is extremely competitive with modern dGPUs, only a bit behind a 6900 XT.

>The M1 is extremely competitive with modern dGPUs, only a bit behind a 6900 XT. Do you have a source for this?

Apple compares the M1 Max as having similar performance to a nVidia's 3080 Laptop GPU, which scores around 16,500 on passmark. For comparison, the AMD 6900 XT desktop CPU scores 27,000, while the nVidia 3080 desktop GPU scores 24,500.

So the M1 Max is not as fast as a high end desktop GPU. Still, it is incredible that you are getting a GPU that performs slightly less than a last generation 2080 desktop GPU at just 50-60 watts.

Re: Apple’s new M1 Pro and M1 Max processors

#788
post #756

Earlier quoted context omitted.

Still confused how 32 core M1 Max competes with Nvidia's thousands-of-cores GPUs. Certainly there are some things that are nearly linear with core count, or otherwise they wouldn't keep adding cores, right? Edit: Found answer here. GPU core is not the same thing as a CUDA core. https://www.reddit.com/r/hardware/comments/73i3ne/why_do_app...

The desktop RTX 3070 has 46 SMs, which are the most comparable thing to Apple's cores. NVIDIA defines any SIMD lane to be a core. They recently have gotten more creative with definition, they were able to double FP32 executions per unit (versus previous gen) and hence in marketing materials, doubled the number of "CUDA cores".

Funny, all these years I've been wondering how they possibly packed so many "cores" into those things.

Re: Apple’s new M1 Pro and M1 Max processors

#790
post #167

It’s interesting that the M1 Max is similar in GPU performance to RTX 3080. A sub $1000 Mac Mini would end up being the best gaming PC you could buy, at less than half the price of an equivalent windows machine.

The M1 Max starts at $2700 for the 16" 10-core CPU, 24-core GPU. The comparison to higher end graphics uses the M1 Max 32-core GPU which starts at $3500. I'm not seeing a way for a Mac Mini to have the M1 Max, and still be priced below $1000.

While not that big of difference, the 14" is a little cheaper:

* The 14" MBP with M1 Max 10-core CPU, 24-core GPU, 32gb memory is $2,900

* The 14" MBP with M1 Max 10-core CPU, 32-core GPU, 32gb memory is $3,100.

The Mac mini with the Max variant chip will certainly be more than $1,000. But I expect it will be more reasonable than the MBPs, maybe $2,100 for the 32-core GPU version with 32gb of memory. That's how much the currently available Intel 6-core i7 Mac mini with 32gb of memory and 1TB of storage costs.

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