docks USB C Docks, displays and data transfer are impossibly confusing

[BlueMischief]

I tried looking at all the USB specifications but it is insanely confusing to me especially since most of the marketing just blatently says "connect your 4k display at 60Hz and have some 5Gbps USB ports as well!"

I read the guide for display adapters in the forum, but tbh it didn't clear up anything for me.
 

Some background information:

I have a Lenovo Legion 15ahr05, which has 1 USB C 3.2 Gen 1 output that supports DP1.2.

I want to have it so I only need to plug in power and that dock when I come home from work or university. (My laptop does not support USB C charging).
In this dock I want to add my 3440x1440 display, which can run at a absolute maximum of 133Hz with DP1.2 (max spec for HBR2 according to Wiki/DisplayPort).

Alongside the monitor I want the dock to have my peripherals such as mouse, DAC, USB mic, steam controller dongle, and a 1Gbps ethernet link to my server.

Do Docks even work at any reasonable USB speed next to monitors?
Do I need to set my display to 120Hz (not a problem) to free up bandwith for the USB devices/Ethernet?
What should I expect in terms of "leftover transfer speeds" when plugging in lets say a USB ssd, or high bitrate audio devices?

Thanks for the help in advance, I'm at my wits end

[DarkSwordsman]

1. Most marketing is going to BS what it actually does and they will often not provide actual specifications for the hardware
2. The USB specs are confusing, especially with 3.0 and 3.1 being given 3.2 Gen names
3. There's a good chance you won't even know if the motherboard/controller you're using even has enough bandwidth or switching capacity

Basically: The only true way to make sure it works is to buy it and test it. There is a good chance you will be able to get what you want, but it will come at some cost.

Though there may be advice others have that can help you. I've kinda just given up on it.

This is also a video Linus did about USB 4.0 and other compatibility, which is relevant to 3.2 and others still I think.
 

 

[Glenwing]

2 hours ago, BlueMischief said:

I tried looking at all the USB specifications but it is insanely confusing to me especially since most of the marketing just blatently says "connect your 4k display at 60Hz and have some 5Gbps USB ports as well!"

I read the guide for display adapters in the forum, but tbh it didn't clear up anything for me.
 

Some background information:

I have a Lenovo Legion 15ahr05, which has 1 USB C 3.2 Gen 1 output that supports DP1.2.

I want to have it so I only need to plug in power and that dock when I come home from work or university. (My laptop does not support USB C charging).
In this dock I want to add my 3440x1440 display, which can run at a absolute maximum of 133Hz with DP1.2 (max spec for HBR2 according to Wiki/DisplayPort).

Alongside the monitor I want the dock to have my peripherals such as mouse, DAC, USB mic, steam controller dongle, and a 1Gbps ethernet link to my server.

Do Docks even work at any reasonable USB speed next to monitors?
Do I need to set my display to 120Hz (not a problem) to free up bandwith for the USB devices/Ethernet?
What should I expect in terms of "leftover transfer speeds" when plugging in lets say a USB ssd, or high bitrate audio devices?

Thanks for the help in advance, I'm at my wits end

USB-C can operate in two configurations:

 

1. 4 lanes for video, which gives you a full DisplayPort connection, plus USB 2.0 transfer. This will be necessary for 3440 × 1440 >60 Hz if the dock only supports HBR2. But USB 2.0 will only give you the standard 480 Mbit/s for "leftover" data transfer.
2. 2 lanes for video, and 2 lanes of superspeed USB. This will give you half the normal DisplayPort bandwidth, but allows USB data transfers at 5 Gbit/s (for Gen 1 devices) or 10 Gbit/s (for Gen 2 devices).

Or in other words, if you require superspeed USB data transfer, you will only get half the normal bandwidth of the DisplayPort protocol. For HBR3 docks, half bandwidth is enough for 4K 60 Hz while supporting 5 Gbit/s or 10 Gbit/s USB at the same time, but not for HBR2 docks.

[BlueMischief]

39 minutes ago, Glenwing said:

USB-C can operate in two configurations:

1. 4 lanes for video, which gives you a full DisplayPort connection, plus USB 2.0 transfer. This will be necessary for 3440 × 1440 >60 Hz if the dock only supports HBR2. But USB 2.0 will only give you the standard 480 Mbit/s for "leftover" data transfer.
2. 2 lanes for video, and 2 lanes of superspeed USB. This will give you half the normal DisplayPort bandwidth, but allows USB data transfers at 5 Gbit/s (for Gen 1 devices) or 10 Gbit/s (for Gen 2 devices).

My dock supports more, but my host does not. How do I set/force it to the 4lane DP + USB 2.0, I rather have 480Mbps of shared bandwith for ethernet/audio/mouse (option 1) than option 2