4 ms·

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

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

rickbutton 6y ago
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.
- eli 6y ago
  It's a limitation of the M1 chip apparently https://appleinsider.com/articles/20/11/11/how-apple-silicon-on-a-m1-mac-changes-monitor-support-and-what-you-can-connect https://appleinsider.com/articles/20/11/11/how-apple-silicon...
  - dawnerd 6y ago
    That’s merely speculation as to why.
- rorykoehler 6y ago
  You can use sidecar with an ipad for a second external display.
  - Fnoord 6y ago
    With some iPads. Not all. I was thinking of using an older iPad for this purpose, but alas. Won't work. Too old.
- kalleboo 6y ago
  The embedded GPU doesn't support it
reaperducer 6y ago
max 2 displays (only 1 external for laptops) I wonder if that includes AirPlay screens, or just wired.
- Joeri 6y ago
  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.
- kalleboo 6y ago
  I would imagine just wired - it's probably a lack of DisplayPort/HDMI encoders rather than rendering resources.
jrobn 6y ago
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.
simcop2387 6y ago
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.
- dwaite 6y ago
  I don't quite get how Apple could claim to be Thunderbolt-compatible with this sort of limitation in hardware, though.
  - djxfade 6y ago
    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
- SXX 6y ago
  AMD GPUs work just fine with POWER8 hardware so this is certainly solved.
- marcan_42 6y ago
  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.

rickbutton 6y ago

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.

eli 6y ago
It's a limitation of the M1 chip apparently https://appleinsider.com/articles/20/11/11/how-apple-silicon-on-a-m1-mac-changes-monitor-support-and-what-you-can-connect https://appleinsider.com/articles/20/11/11/how-apple-silicon...
- dawnerd 6y ago
  That’s merely speculation as to why.
rorykoehler 6y ago
You can use sidecar with an ipad for a second external display.
- Fnoord 6y ago
  With some iPads. Not all. I was thinking of using an older iPad for this purpose, but alas. Won't work. Too old.
kalleboo 6y ago
The embedded GPU doesn't support it

reaperducer 6y ago

max 2 displays (only 1 external for laptops) I wonder if that includes AirPlay screens, or just wired.

Joeri 6y ago
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.
kalleboo 6y ago
I would imagine just wired - it's probably a lack of DisplayPort/HDMI encoders rather than rendering resources.

jrobn 6y ago

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.

simcop2387 6y ago

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.

dwaite 6y ago
I don't quite get how Apple could claim to be Thunderbolt-compatible with this sort of limitation in hardware, though.
- djxfade 6y ago
  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
SXX 6y ago
AMD GPUs work just fine with POWER8 hardware so this is certainly solved.
marcan_42 6y ago
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.