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Comment by the_pwner224 | Hacker News Reader

Lots of Dell monitors support this - probably every single currently-in-production Ultrasharp supports it, and I think some of the lower tier non-Ultrasharps may support it as well.

Dell monitors all support DDC, I'm not sure if KVM switching can be controlled over DDC but it's likely.

Somewhat unrelated, but some of the Dell monitors also have USB-C support, where a single USB-C cable connects to your laptop and: charges it (Power Delivery from the monitor), hooks up the display (DP alt mode), and connects to the USB hub on the monitor. So if you use a wireless kb/mouse with receivers plugged into the monitor, you'll have literally just 2 cables on your desk - a power cable for your monitor, and a USB-C cable between the monitor and laptop.

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For me, you want 2 more wires:

- the laptop to the side is awkwardly positioned for zoom chat, so you probably want a webcam as well

- audio is a problem. If you use bluetooth and swap lots of things over then you keep needing to re-pair which is a pain. The model I have (Dell UltraSharp 27 USB-C Hub Monitor - U2722DE) has an audio jack but this is for connecting to soundbars not headphones, and the soundbars Dell offered that are compatible with that monitor don't support headphones. So, I ended up using a USB headset. You can use bluetooth with a usb soundcard dongle to avoid swapping, but bidirectional sound is an issue with that so you'll want to use the mic on the webcam (if you got one like that)

My keyboard/trackball are wired to the monitor, there doesn't seem to be much point to having wireless to attach something that's only a foot away anyway.

Either way, it's one connection to the laptop, but 4-5 other things need to connect to the monitor too. Still pretty good and not too much clutter tho

> I'm not sure if KVM switching can be controlled over DDC but it's likely.

They do. Here's my shell function that helps me switch between DisplayPort-1 + USB uplink cable to the host AND USB-C cable with DisplayPort Alt Mode+Charging+uplink to display's USB hub.

  # x0f: DisplayPort-1
  # x1b: USB-C
  DDC_SOURCES=("x0f" "x1b")

  switchkvm() {
    local vcp_input_src="x60"
    local current next src
    current=$(ddcutil -t getvcp ${vcp_input_src} | awk '{ print $4 }')
    for src in "${DDC_SOURCES[@]}"; do
      if [[ ${src} != "${current}" ]]; then
        next=${src}
      fi
    done
  
    if [[ -z ${next} ]]; then
      echo "No eligible alternate input in \$DDC_SOURCES" >&2
      echo "\$DDC_SOURCES=(${DDC_SOURCES[*]}); current=${current}"
      return 1
    fi

    ddcutil setvcp "${vcp_input_src}" "${next}"
  }

Thanks for sharing that - its very useful to know that there is a way to do this, I just need to select the right hardware ..

+1, I recently got a Dell and it works great.

I have a desktop Linux PC but I often need to switch to my MacBook. If I plug the MacBook in, all my peripherals automatically switch to it. If I unplug, everything switch he's back to the Linux PC.

You can definitely use DDC to switch inputs, and the KVM is linked to the selected input. On MacOS I use Better Display which lets me switch inputs from a menu bar app. On linux there is ddcui (which is more like a proof of concept than a polished app, but it works). It's rare that I need to use this though since the auto-switching is usually all I need.

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