• narc0tic_bird@lemm.ee
    link
    fedilink
    English
    arrow-up
    10
    arrow-down
    1
    ·
    2 months ago

    What you’re describing as “DisplayPort alt mode” is DisplayPort Multi-Stream Transport (MST). Alt mode is the ability to pass native DisplayPort stream(s) via USB-C, which all M chip Macs are capable of. MST is indeed unsupported by M chip hardware, and it’s not supported in macOS either way - even the Intel Macs don’t support it even though the hardware is capable of it.

    MST is nice for a dual WQHD setup or something (or dual UHD@60 with DisplayPort 1.4), but attempt to drive multiple (very) high resolution and refresh rate displays and you’ll be starved for bandwidth very quickly. Daisy-chaining 6 displays might technically be possible with MST, but each of them would need to be set to a fairly low resolution for today’s standards. Macs that support more than one external display can support two independent/full DisplayPort 1.4 signals per Thunderbolt port (as per the Thunderbolt 4 spec), so with a proper Thunderbolt hub you can connect two high resolution displays via one port no problem.

    I agree that even base M chips should support at least 3 simultaneous displays (one internal and two external, or 3 external in clamshell mode), and they should add MST support for the convenience to be able to connect to USB-C hubs using MST with two (lower-resolution) monitors, and support proper sub-pixel font anti-aliasing on these low-DPI displays (which macOS was perfectly capable of in the past, but they removed it). Just for the convenience of being able to use any random hub you stumble across and it “just works”, not because it’s necessarily ideal.

    But your comparison is blown way out of proportion. “Max” Macs support the internal display at full resolution and refresh rate (120 Hz), 3 external 6K 60Hz displays and an additional display via HDMI (4K 144 Hz on recent models). Whatever bandwidth is left per display when daisy-chaining 6 displays to a single Thunderbolt port on a Windows machine, it won’t be anywhere near enough to drive all of them at these resolutions.

    • masterspace@lemmy.ca
      link
      fedilink
      English
      arrow-up
      2
      ·
      edit-2
      2 months ago

      Agreed, I typed quickly before bed and meant MST not alt mode.

      But otherwise you’re just arguing that it’s not a big deal because ‘you don’t need any of these fancy features if you throw out your monitor every three years and buy new thousand dollar ones’.

      For everyone who doesn’t want to contribute to massive piles of e-waste, we still have 1080p and 1440p, 60Hz monitors kicking around, and there is no excuse for a Mac to only be able to drive one of them with crappy looking text. It could easily drive 6 within the bandwidth of a 4k, 120Hz signal. Hell it could drive 8 or more if you drop the refresh down to 30.

      • narc0tic_bird@lemm.ee
        link
        fedilink
        English
        arrow-up
        2
        ·
        2 months ago

        I’m not generally arguing it’s not a big deal. I’m actually saying the regular M chips should be upgraded to M “Pro” levels of display support. But beyond two external displays, yes, I’m arguing it’s not a big deal, simply because >99% of users don’t want to use more than two external displays (no matter the resolution). Even if I had 6 old displays lying around I would hardly use more than two of them for a single computer. And as long as I’m not replacing all 6 displays with 6 new displays it doesn’t make a difference in terms of e-waste. On the contrary I’d use way more energy driving 6 displays simultaneously.

        I’m 100% with you that MST should be supported, but not because driving six displays (per stream) is something I expect many people to do, but because existing docking solutions often use MST to provide multiple (2) DisplayPort outputs. My workplace has seats with a USB-C docking station connected to two WQHD displays via MST, and they’d all need replacing should we ever switch to MacBooks.

        And sure, they should bring back proper font rendering on lower resolution displays. I personally haven’t found it to be too bad, but better would be … better, obviously. And as it already was a feature many moons ago, it’s kind of a no-brainer.