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The Thunderbolt capable docks on Amazon are still listed as USB-C because consumers seem to think it’s all about cable shape. That said, there are plenty of du

The Thunderbolt capable docks on Amazon are still listed as USB-C because consumers seem to think it’s all about cable shape. That said, there are plenty of dual USB-C connector, dual HDMI 4K@60hz port, dongles designed for Mac on Amazon. I think this is the most recent addition: https://smile.amazon.com/gp/product/B07RH9HF4R/ https://smile.amazon.com/gp/product/B07RH9HF4R/ ”Satechi Aluminum Type-C Dual HDMI Adapter 4K 60Hz with USB-C PD Charging — Stunning dual HDMI display with a convenient USB-C PD port to keep your setup up and running - all in 4K 60Hz resolution. ENGINEERED FOR 4K DUAL DISPLAY - features dual HDMI ports to connect two monitors for stunning, extended 4K 60Hz display. Requires a direct HDMI connection, will not work with VGA, DVI or Thunderbolt displays...” By contrast, this is one HDMI 4K@60Hz and one HDMI 4K@30Hz: https://smile.amazon.com/Satechi-Multimedia-Adapter-Gigabit-Ethernet/dp/B07RH8L9GV/ https://smile.amazon.com/Satechi-Multimedia-Adapter-Gigabit-... Includes the two 4K HDMI ports of differing refresh rates, USB-C PD 3.0 charging, Gigabit Ethernet, micro/SD card readers, and USB 3.0 ports, and also will not work with Thunderbolt.

chx 7y ago
Two 4k @ 60 Hz is either Thunderbolt (which is fine for Macs but has a price and I would rather buy like https://www.monoprice.com/product?p_id=38575 https://www.monoprice.com/product?p_id=38575 or https://www.monoprice.com/product?p_id=31261 https://www.monoprice.com/product?p_id=31261 instead of a noname company) or DisplayLink which is to be avoided at all costs. This hub is Thunderbolt as can be deciphered from "Does not support MacBook models with single USB-C port" (see https://support.apple.com/en-us/HT201736#usbc https://support.apple.com/en-us/HT201736#usbc ) but the fact I need to decipher what it is a second strike against it. It seems lately Intel has loosened its iron grip on Thunderbolt 3 (after all, it handed the standard over to USB IF) so now everything goes (we see empty M.2 to TB3 enclosures and chaining eGPU boxes both of which were forbidden by Intel prior) but the fact they didn't include the trademarked name makes me go hm. Finally, it could be a DP 1.4 MST hub but that is very rare (the first USB C to DP 1.4 MST I am aware of was announced at CES 2020 https://plugable.com/2020/01/07/plugables-new-docking-station-and-adatpers-at-ces-2020-raise-the-bar-for-connectivity-power-and-productivity/ https://plugable.com/2020/01/07/plugables-new-docking-statio... and didn't ship yet) and figuring out support will be _very_ interesting. All Intel 14nm laptop CPUs are stuck with DisplayPort 1.2 and then researching which laptops with Radeon / nVidia GPUs run their USB C through those GPUs to provide DP 1.4 will be fun. Let's put 4k @ 60 (and then 4k @ 30) into the bandwidth calculator: https://linustechtips.com/main/topic/729232-guide-to-display-cables-adapters-v2/?section=calc&H=3840&V=2160&F=60&calculations=show https://linustechtips.com/main/topic/729232-guide-to-display... you can see you need more than what DP 1.2 can provide so everything I said above applies. Oh and of course if it's for a Mac, in general, you could just use two USB C plugs, I suspect that's what the 4k @ 60 + 4k @ 30 is: one plug is used in DP alt mode, the other is used in MFDP mode.
- Terretta 7y ago
  It doesn’t support macs with a single port because it takes two ports, uses each one. That changes the bandwidth calculator math. This adapter was, I believe, also announced at CES 2020.
  - chx 7y ago
    Oh I see now https://images-na.ssl-images-amazon.com/images/I/71z-IlmfZeL._AC_SL1500_.jpg https://images-na.ssl-images-amazon.com/images/I/71z-IlmfZeL... the single plug misled me to think it's just one USB C. Crafty.
- akiselev 7y ago
  Intel may have ostensibly handed the standard over to USB IF but all of the reference designs you'd use to implement a Thunderbolt dock are behind NDAs and unavailable [1] unless you get lucky, have an existing relationship, or have the volume to get their attention. [1] https://thunderbolttechnology.net/developer-application https://thunderbolttechnology.net/developer-application
  - chx 7y ago
    Yeah but it used to be that Intel needed to certify every TB3 device and they wouldn't certify a PCIe enclosure as eGPU if it chained. Neither they would an empty M.2 key M enclosure. Both now exist.
- bloopernova 7y ago
  > or DisplayLink which is to be avoided at all costs May I ask why, or is it the details you have later in your post?
  - xmodem 7y ago
    DisplayLink transports video over the USB bus, rather than using one of the alt modes of USB-C. As you can imagine, this introduces compression artefacts and substantial CPU overhead. It's passable for web browsing. Watching any sort of video is painful and forget about any sort of gaming or latency sensitive application
maxsilver 7y ago
Sorry, to clarify, you technically can get enough bandwidth for 4k@60hz out of a USB-C port, but you have to abandon the data lanes for more DisplayPort lanes. (I.e, give up all of your USB 3.0 ports and gigabit ethernet or similar-speed ports). So, "adapters" can do it, but docks generally can't. https://www.bigmessowires.com/2019/05/19/explaining-4k-60hz-video-through-usb-c-hub/ https://www.bigmessowires.com/2019/05/19/explaining-4k-60hz-... has the specific technical details.
- Terretta 7y ago
  Yes, that link was in my top level post. :-) And that’s why I’m linking to adapters that use two of the Macbook Pro ports.
- lxgr 7y ago
  That‘s not generally true. Apple‘s newer model multiport adapter does 4k60 and USB 3 on devices supporting DisplayPort 1.3 (which is required to fit 4k60 into two instead of four lanes).
  - p_l 7y ago
    That's the magic of displayport for you. It won't do that on HDMI, except with active converted from DP to HDMI :)
    - lxgr 7y ago
      I'd assume that all of these hubs are using DisplayPort though? HDMI alternate mode hasn't really caught on, especially since it uses all high-speed lanes on USB-C. This leaves no room for USB 3 ports on a combined hub.
s_gourichon 7y ago
Satechi always sounds funny to French people. Pronouncing the name literally means in casual language "it poops you".
- jvzr 7y ago
  Never realized that until you mentioned it. And I've owned some of their products for a long time. I guess it's because I figured it was pronounced "satéchi" which is more likely sound for an Asian company ("saké" and not "sakeuh")
Marsymars 7y ago
> The Thunderbolt capable docks on Amazon are still listed as USB-C because consumers seem to think it’s all about cable shape. Thunderbolt docks with Titan Ridge controllers fall back to USB capabilities/bandwidth if connected to a USB-C non-Thunderbolt host.
dehrmann 7y ago
> consumers seem to think it’s all about cable shape. As others have noted, the Thunderbolt/USB landscape is pretty confusing.

chx 7y ago

Two 4k @ 60 Hz is either Thunderbolt (which is fine for Macs but has a price and I would rather buy like https://www.monoprice.com/product?p_id=38575 https://www.monoprice.com/product?p_id=38575 or https://www.monoprice.com/product?p_id=31261 https://www.monoprice.com/product?p_id=31261 instead of a noname company) or DisplayLink which is to be avoided at all costs. This hub is Thunderbolt as can be deciphered from "Does not support MacBook models with single USB-C port" (see https://support.apple.com/en-us/HT201736#usbc https://support.apple.com/en-us/HT201736#usbc ) but the fact I need to decipher what it is a second strike against it. It seems lately Intel has loosened its iron grip on Thunderbolt 3 (after all, it handed the standard over to USB IF) so now everything goes (we see empty M.2 to TB3 enclosures and chaining eGPU boxes both of which were forbidden by Intel prior) but the fact they didn't include the trademarked name makes me go hm. Finally, it could be a DP 1.4 MST hub but that is very rare (the first USB C to DP 1.4 MST I am aware of was announced at CES 2020 https://plugable.com/2020/01/07/plugables-new-docking-station-and-adatpers-at-ces-2020-raise-the-bar-for-connectivity-power-and-productivity/ https://plugable.com/2020/01/07/plugables-new-docking-statio... and didn't ship yet) and figuring out support will be _very_ interesting. All Intel 14nm laptop CPUs are stuck with DisplayPort 1.2 and then researching which laptops with Radeon / nVidia GPUs run their USB C through those GPUs to provide DP 1.4 will be fun. Let's put 4k @ 60 (and then 4k @ 30) into the bandwidth calculator: https://linustechtips.com/main/topic/729232-guide-to-display-cables-adapters-v2/?section=calc&H=3840&V=2160&F=60&calculations=show https://linustechtips.com/main/topic/729232-guide-to-display... you can see you need more than what DP 1.2 can provide so everything I said above applies. Oh and of course if it's for a Mac, in general, you could just use two USB C plugs, I suspect that's what the 4k @ 60 + 4k @ 30 is: one plug is used in DP alt mode, the other is used in MFDP mode.

Terretta 7y ago
It doesn’t support macs with a single port because it takes two ports, uses each one. That changes the bandwidth calculator math. This adapter was, I believe, also announced at CES 2020.
- chx 7y ago
  Oh I see now https://images-na.ssl-images-amazon.com/images/I/71z-IlmfZeL._AC_SL1500_.jpg https://images-na.ssl-images-amazon.com/images/I/71z-IlmfZeL... the single plug misled me to think it's just one USB C. Crafty.
akiselev 7y ago
Intel may have ostensibly handed the standard over to USB IF but all of the reference designs you'd use to implement a Thunderbolt dock are behind NDAs and unavailable [1] unless you get lucky, have an existing relationship, or have the volume to get their attention. [1] https://thunderbolttechnology.net/developer-application https://thunderbolttechnology.net/developer-application
- chx 7y ago
  Yeah but it used to be that Intel needed to certify every TB3 device and they wouldn't certify a PCIe enclosure as eGPU if it chained. Neither they would an empty M.2 key M enclosure. Both now exist.
bloopernova 7y ago
> or DisplayLink which is to be avoided at all costs May I ask why, or is it the details you have later in your post?
- xmodem 7y ago
  DisplayLink transports video over the USB bus, rather than using one of the alt modes of USB-C. As you can imagine, this introduces compression artefacts and substantial CPU overhead. It's passable for web browsing. Watching any sort of video is painful and forget about any sort of gaming or latency sensitive application

maxsilver 7y ago

Sorry, to clarify, you technically can get enough bandwidth for 4k@60hz out of a USB-C port, but you have to abandon the data lanes for more DisplayPort lanes. (I.e, give up all of your USB 3.0 ports and gigabit ethernet or similar-speed ports). So, "adapters" can do it, but docks generally can't. https://www.bigmessowires.com/2019/05/19/explaining-4k-60hz-video-through-usb-c-hub/ https://www.bigmessowires.com/2019/05/19/explaining-4k-60hz-... has the specific technical details.

Terretta 7y ago
Yes, that link was in my top level post. :-) And that’s why I’m linking to adapters that use two of the Macbook Pro ports.
lxgr 7y ago
That‘s not generally true. Apple‘s newer model multiport adapter does 4k60 and USB 3 on devices supporting DisplayPort 1.3 (which is required to fit 4k60 into two instead of four lanes).
- p_l 7y ago
  That's the magic of displayport for you. It won't do that on HDMI, except with active converted from DP to HDMI :)
  - lxgr 7y ago
    I'd assume that all of these hubs are using DisplayPort though? HDMI alternate mode hasn't really caught on, especially since it uses all high-speed lanes on USB-C. This leaves no room for USB 3 ports on a combined hub.

s_gourichon 7y ago

Satechi always sounds funny to French people. Pronouncing the name literally means in casual language "it poops you".

jvzr 7y ago
Never realized that until you mentioned it. And I've owned some of their products for a long time. I guess it's because I figured it was pronounced "satéchi" which is more likely sound for an Asian company ("saké" and not "sakeuh")

Marsymars 7y ago

> The Thunderbolt capable docks on Amazon are still listed as USB-C because consumers seem to think it’s all about cable shape. Thunderbolt docks with Titan Ridge controllers fall back to USB capabilities/bandwidth if connected to a USB-C non-Thunderbolt host.

dehrmann 7y ago

> consumers seem to think it’s all about cable shape. As others have noted, the Thunderbolt/USB landscape is pretty confusing.