M1 ultrafusion, the most powerful chip in Apple's history

On the surface, M1 ultra is two M1 Max connected together through the chip to chip connector of ultrafusion. The connector itself is very powerful: with a chip to chip bandwidth of 2.5tb/s, the two M1 Max can be logically regarded as a large M1 Ultra.


  1. M1 ultra is the latest SOC released by apple in March 2022 and debuted on the new Mac studio

  2. Basically speaking, M1 ultra is connected between two M1 max, so it has double things: 20 computer cores, 2 neural engines, 64 graphics cores, 4 media engines and 800 MB / s memory bandwidth

  3. Technical details: there is a chip to chip bridge that is micro stitched together, called ultrafusion. The chip to chip bandwidth is 2.5 TB / s

  4. According to the patent investigation results, apple is considering adding more chips in the 3D stacking style and using this kind of micro stitching, which is expected to make its debut in the updated Mac Pro.

M1 ultra layout

Having two or more physical CPUs or symmetric multiprocessing (SMP) is nothing new. However, there are many defects in having dual physical processors, so the industry generally turns to multi-core systems. Apple can weld the dual M1 Max on a board and complete the design, but using hyperfusion has more performance advantages than installing the dual M1 max.

Ultrafusion is a bridge connecting two M1 Max

Since M1 ultra is essentially a combination of two M1 max, it has twice the content of M1 Max: 20 computing cores (16 performance and 4 efficiency), 2 neural engines, a total of 32 neural cores, up to 64 core graphics cores and 4 media engines. It can stream 16 and 16 8K prores 422 video streams in Final Cut Pro. The uniqueness of the layout lies in how the graphics cores are arranged adjacent to each other, so the data related to graphics processing is bundled together instead of being transferred from one end of the chip to the other.

Another feat is a memory bandwidth of about 800MB / s. Based on 6.4 GB / s per 8-bit channel, the M1 ultra should have about 16 channels to reach the amazing 800 GB / s bandwidth. Intel's high-end chips (such as i9-12900k) have only two channels with a memory bandwidth of 76.8gb/s, while the more high-end Xeon w-3375 has eight memory channels on DDR4, which should be converted to a memory bandwidth of about 200GB / s. M1 ultra has about 128GB of available RAM and can access the entire memory library 6 times per second.

M1 ultra features described by Apple

M1's feat is not only memory, but also I / O bandwidth. After all, we need to obtain and present data from the outside through linkage. In M1 ultra MAC studio, there are 6 thunderbolt 4 ports, and each port has its own controller. This means that each thunderbolt 4 port in MAC studio has a full 40Gb / s bandwidth dedicated to each port. Therefore, only for the thunderbolt port, there is a total of 240 GB / s bandwidth. There are also 10GB Ethernet, HDMI 2.0 port and traditional usb-a port, which should provide about USB 3.1 Gen 2 speed. This is why MAC studio can support four 6K monitors (such as pro display XDR) and one 4K TV. M1 ultra is a very powerful SOC, although it handles a lot of bandwidth and processing capacity. But according to apple, the CPU consumes about 60 watts, while the GPU consumes about 100 to 120 watts.

M1 series SOC as of March 2022


Here, M1 ultra is compared with Intel i9-12900k.

Geekbench test shows that M1 ultra lags behind Intel i9-12900k in multi-core performance, but it is another matter in cinebench.

In terms of CPU, Intel i9-12900k performs better in single core tasks, while M1 ultra performs better in multi-threaded tasks because it has more cores than Intel. Intel made great progress in its 12th generation core processor and successfully beat the M1 Max chip. However, apple won the competition again with its M1 ultra processor, which beat Intel's processor in multi-core tasks.

    According to apple, under a given power consumption (300), M1 ultra is more efficient and powerful than NVIDIA RTX 3090. However, it is not said that the RTX 3090 needs to consume 400-600 watts to obtain the required performance. Apple is playing a word game. In short, if the work is suitable for the apple ecosystem, the M1 ultra is the most powerful chip Apple has ever had.

M1 ultra has the most powerful integrated GPU so far, but PC manufacturers prefer to rely on NVIDIA's discrete solutions.

  So far, M1 ultra is the most powerful chip designed by apple. It is true that many people will not touch the upper limit provided by M1 Ultra. However, apple can show intel, AMD and NVIDIA that they have a new competition. After all, good competition can make each company better.

source: Shell breaking science popularization Society