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October 18th 2021 Apple Event: M1 Pro/Max MacBook Pros

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True, the main question to ask is: Do I need to pay that much extra for memory bandwidth, graphics cores and GPU cores that I might possibly not even use ? The M1 Pro choice should work for the majority of people.
Agreed. In fact even the base configuration would be plenty powerful. If last year's M1 MacBook Pros had such stellar performance and this year's entry level exceeds that in every way, why wouldn't it be more than sufficient?

Ultimately, my decision was a compromise between the left brain and the right brain, between need and want. Apple has released a machine that exceeded my expectations so "voting with my wallet" is a clear message of support and enthusiasm to Apple.

When AMD released the Ryzen 9 5950X with 16 cores and 32 threads, a lot of enthusiasts rushed to it despite not needing it... That was also a message of support and enthusiasm. ;)
 
Exciting technology, but expensive.

The machine I want didn't happen (these new guts inside a Mac Mini form factor)
 
The M1 Max has these advantages over M1 Pro:
  • 24-core and 32-core GPU options. M1 Pro is limited to 16-core GPU.
  • 400GB/s memory bandwidth versus 200GB/s on M1 Pro.
I suppose that the doubled bandwidth only applies with doubled memory. A 32 GB M1 Max is probably limited to 200 GB/s just like a 32 GB M1 Pro.
Now let's wait for the reviews and technical analysis of these chips…
 
I suppose that the doubled bandwidth only applies with doubled memory. A 32 GB M1 Max is probably limited to 200 GB/s just like a 32 GB M1 Pro.
Now let's wait for the reviews and technical analysis of these chips…
Yes good point. There are two possibilities as shown below:
  • Option 1: 32GB can be made from four 8GB modules, hence quad-channel 400GB/s
  • Option 2: 32GB can be made from two 16GB modules, hence dual-channel 200GB/s
My guess is option 2, which would bring the speed down to 200GB/s.

Screen Shot 2021-10-18 at 2.21.21 PM.png
 
There are two possibilities as shown below:
According to Tom's hardware and other sources, the M1s use 8 channel DDR4. Wouldn't M1 Pro and Max also ?
To feed the more powerful CPU and GPU subsystems with enough data, the M1 uses a 128-bit eight-channel LPDDR4X-4266 memory subsystem (up from a quad-channel 64-bit memory subsystem in the A14). Apple also shrunk the system level cache by 25%, which is logical given that the memory subsystem became more powerful.
 
Until I can run a Windows VM in VMware Fusion, no Apple silicon for me.
Maybe Rosetta 2 will work well enough on these new MBPs to allow better performance for a Windows VM.
 
I’m much more interested to see GPU comparisons honestly.
The CPUs being great isn’t that surprising
 
According to Tom's hardware and other sources, the M1s use 8 channel DDR4. Wouldn't M1 Pro and Max also ?
Yes the M1 Pro and M1 Max likely have the same 8-channel memory bus per memory "chiplet".
  • M1 has two small memory chiplets.
    • Comes in 8GB or 16GB capacity.
    • 8GB is presumably delivered by one chiplet, while the other is disabled.
    • But there's just one memory bus.
      Screen Shot 2021-10-18 at 3.13.23 PM.png
  • M1 Pro has two large memory chiplets.
    • For 16GB, is one chiplet disabled?
    • For 16GB, does each chiplet contribute 8GB?
    • There are two memory buses.
      Screen Shot 2021-10-18 at 3.14.41 PM.png
  • M1 Max has four large memory chiplets.
    • For 32GB, are two chiplets disabled?
    • For 32GB, does each chiplet contribute 8GB?
    • There are four memory buses.
      Screen Shot 2021-10-18 at 3.17.31 PM.png
In the video, Johny Srouji states that M1 Pro "doubles the width of the memory interfaces and uses faster DDR4". This might just mean that there is a second full-size memory bus targeting the second large chiplet. And on the M1 Max, this doubles again because the same full-size bus is duplicated for each of the 4 large memory chiplets.

So although the channel width per chiplet may be the same as on M1, the fact that it is duplicated once for each chiplet would account for the higher bandwidths:
  • M1 = 1 memory bus = 100GB/s bandwidth
  • M1 Pro = 2 buses = 200GB/s
  • M1 Max = 4 buses = 400GB/s
P.S. This is just my best guess.
 
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