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A comment on Apple Silicon M1 chip in MacBook Air outperforms high-end 16-inch MacBook Pro. Parent comment

Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by kalleboo on Wednesday November 11, 2020 @09:48PM (#25065858)
It still has a lot of limitations that matter to many pros - max 16 GB of RAM, max 2 displays (only 1 external for laptops), only enough PCIe lanes to support 2 thunderbolt ports. eGPUs aren't supported either, but hopefully that is a software thing that will be fixed.

It will be very interesting to see what the performance will be of the more "pro" chip that overcomes those limitations that they'd put in the 16" and iMacs

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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by jrobn on Wednesday November 11, 2020 @11:41PM (#25066519)
It’s a first generation chip in a thin-and-light laptop. I suspect all those problems will be fixed as they scale it up. Not to mention their unique position of leverage dedicated acceleration silicon in their software now.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by simcop2387 on Wednesday November 11, 2020 @11:57PM (#25066601)
eGPU support will depend on if they have a way to work around the need for a PCIe I/O BAR. Many GPUs require that to initialize and as far as I know no ARM cpus support it since it's a legacy-ish x86 thing. It'll be the same problem that prevents gpu use on raspberry pi 4s still. I bet you can make a controller that'll provide a mapping for that to allow it but that'll mean needing a new enclosure (probably not a huge deal) and new silicon and drivers.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by marcan_42 on Thursday November 12, 2020 @07:36AM (#25069145)
AMD GPUs do not require I/O BARs, and highly doubt Nvidia ones do either. The VBIOS will probably assume it can use it, but most modern cards can be initialized without actually running the VBIOS (because people use them on headless servers, for virtualization, and things like that). The I/O BAR is only required for legacy VGA compatibility, you can ignore it.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by SXX on Thursday November 12, 2020 @05:16AM (#25068351)
AMD GPUs work just fine with POWER8 hardware so this is certainly solved.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by dwaite on Thursday November 12, 2020 @02:37AM (#25067436)
I don't quite get how Apple could claim to be Thunderbolt-compatible with this sort of limitation in hardware, though.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by djxfade on Thursday November 12, 2020 @03:59AM (#25067877)
It's not a limitation in hardware. It's a legacy feature of the x86 that isn't supported on ARM.

This could be solved by the GPU engineers by removing the legacy compatibility. "Nobody" boots a modern PC from BIOS anymore

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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by reaperducer on Wednesday November 11, 2020 @11:19PM (#25066390)
max 2 displays (only 1 external for laptops)

I wonder if that includes AirPlay screens, or just wired.

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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by Joeri on Thursday November 12, 2020 @03:45AM (#25067785)
This may work. On a 2014 macbook air, which officially only supports only one external display, I've been able to use two external screens at the same time by sharing one through airplay. However, you're always limited in resolution and latency that way.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by kalleboo on Thursday November 12, 2020 @05:11AM (#25068323)
I would imagine just wired - it's probably a lack of DisplayPort/HDMI encoders rather than rendering resources.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by rickbutton on Wednesday November 11, 2020 @10:34PM (#25066109)
why would it be only 1 external display? Can you not plug into a thunderbolt dock and use multiple external displays? I do exactly that with my 2012 MacBook Pro.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by eli on Wednesday November 11, 2020 @10:37PM (#25066136)
It's a limitation of the M1 chip apparently

https://appleinsider.com/articles/20/11/11/how-apple-silicon...

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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by dawnerd on Thursday November 12, 2020 @03:39PM (#25074660)
That’s merely speculation as to why.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by rorykoehler on Wednesday November 11, 2020 @10:49PM (#25066214)
You can use sidecar with an ipad for a second external display.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by Fnoord on Thursday November 12, 2020 @04:58AM (#25068254)
With some iPads. Not all. I was thinking of using an older iPad for this purpose, but alas. Won't work. Too old.
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Re:Apple Silicon M1 chip in MacBook Air outperforms high-end... by kalleboo on Wednesday November 11, 2020 @11:28PM (#25066448)
The embedded GPU doesn't support it
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