Connecting Z24u G3 to desktop PC via USB-c / Thunderbolt

[Narbux]

Hi all,

I recently bought 2 Z24u G3 monitors, that I'd like to use with my desktop PC.

If I understand it correctly from the manual, I need to connect 1 monitor to the PC via USB-c in order to enable the USB ports on the monitor, eg for keyboard, mouse and phone charging. My PC doesn't have a Thunderbolt output yet, but I'm planning to create one using a Thunderbolt PCIe expansion card.

My question is: will this setup work? Particularly, both the Z24u and such expansion cards are able to deliver power for charging connected devices, so will connecting them this way lead to problems?

And if this isn't the right way to go, how can I enable the USB functionality on my Z24us when connected to my desktop PC?

Thanks!

[itsmyname]

@Narbux -- there is a limit on how much electrical power that your motherboard can send through any USB port.  If you want to connect multiple devices to the USB ports on the monitor, the question is whether the power for those devices is delivered through the power-adapter that powers your monitor's screen, or whether the power coming through the USB cable is the ONLY source of power for the devices.

Experiment: disconnect the monitor from your computer, and turn the monitor on. Connect a device that charges over USB (such as an older Apple iPhone), and see if the iPhone shows that it is charging, while there is NO connection to your computer.  It is is charging, then the power is coming directly from the monitor, not from the computer.  Turn the monitor off. Does the iPhone show that it is not getting charged?

[Narbux]

Hi @Itsmyname,

thanks a lot for your reply.

My primary concern was actually whether I could damage any of the components (either monitor or PC), by connecting two ports that both provide power delivery. Is this indeed a concern, or will the devices 'auto detect' in which direction the power delivery should flow, if at all?

Thanks again!

[itsmyname]

@Narbux -- USB is a "two-way" protocol, allowing data in both directions, but, probably only allowing "power" to flow one way (from the computer to a keyboard/mouse/webcam/memory-stick).

There probably is NO "auto-detect" for the transmission of power -- USB is designed to flow the power only in one direction. You probably have not given any thought to plugging-in many USB-devices (printers, webcams, scanners, mouse) directly to your PC -"it just works".

If your monitor is receiving AC power from a wall-outlet, it is probable that it is sending power to each of the USB ports on the monitor, i.e., not relying on the computer to "send power".  I did ask you to disconnect the monitor from the computer, to see if the USB devices connected to the monitor will still receive power from "somewhere".

Compare to a "powered" USB-hub, versus a non-powered one. When some devices require higher levels of power than a "non-powered" hub can provide (by "relaying" power from the computer), it is necessary to use a "powered-hub" to provide higher-levels of power to a connected device.

[Narbux]

Hi @Itsmyname,

thank you for the explanation. The reason I hadn't (and still haven't) performed the test you suggest is that I don't have the necessary equipment yet: I haven't bought a Thunderbolt expansion card for my PC yet because I first wanted to make sure that I can't damage any equipment making that connection.

From your answers I get the impression that you would not be worried about that, is that correct?

[itsmyname]

@Narbux -- From your answers, I get the impression that you would not be worried about that.

Yes, that is my opinion. 

To me, it makes sense -- the camera "embedded" in the case that holds the monitor is unusual, but like every other web-camera, it needs to connect to some USB port on the computer, so that the computer can use it.