U2722D, pointless USB-C?

@heidibe  Quick additional notes.  You said that the A to C cable that came with the display didn't work, but you didn't specify exactly how you were using it.  (When asking for technical assistance, it helps to provide technical details like that.) If you used that cable to connect a USB-A port on the display to a USB-C port on your PC, that wouldn't have worked at all because you don't use a downstream port on a display to connect to a source PC.  And if you connected the USB-C downstream port on the display to a USB-A port on the PC, that wouldn't have worked either.  But if you used that A to C cable to connect the display's USB-C upstream port -- again, the one next to the DisplayPort output -- to a USB-A port on your PC, then that would have allowed you to use the other USB ports on the display as a USB hub for that PC.  But that connection wouldn't have allowed video or power to flow between your PC and the display, because that's simply not what that port is designed for.  (Also, USB-A cables can't be used for video or for charging a laptop.)

There's no cable or adapter that you can buy that will allow you to charge your laptop from a U2722D.  An HDMI to HDMI cable won't carry USB data or power, regardless of the display's capabilities.  If you want to charge your laptop from your display, you should return the U2722D and get a U2722DE instead.

Ahhhh, many thanks for explaining! I'm not exactly tech savvy with words, so I got all confused. 

I bought a USB-C monitor with the intention to have a simple USB-C - C cable with my Macbook for personal use, then use HDMI - HDMI on my Lenovo work laptop. Both laptops to display on the monitor. 

I can connect Macbook using HDMI - C cable, but that defeats the purpose as I could've gotten a HDMI only monitor with an adaptor. 

Is U2721DE the same as U2722DE?? As I came across 21DE, but to be honest I'm unsure which part to read which will allow C-C to display (charging is a bonus) also an HDMI port for my different laptop. 

@heidibe Happy to help. The U2722DE is one model year newer than the U2721DE, and it has some enhancements:

• Support for up to 90W power delivery rather than 65W on the 21DE. If you have a 15-16” MacBook Pro or think you might ever want to charge some other laptop that is designed for more than 65W, that would be beneficial to you.
• Support for USB 3.2 Gen 2 (10 Gbps) rather than Gen 1 (5 Gbps) on the 21DE.
• That separate data-only USB-C upstream port. On the 21DE, the only upstream data port is the full-featured USB-C input, which means you wouldn’t be able to have USB data connectivity to two separate systems to make it easy to switch USB devices between them. Since you’ll be using two systems with your display, if you want to be able to plug a keyboard and mouse into USB ports on the display and then use those peripherals with each system depending on which one you’re showing on the display at any given time, then you’d need to have two upstream USB connections and therefore would want the 22DE. The alternative would be to simply use a single USB-C to USB-C cable and move that cable between your MacBook Air and X13 Yoga as needed. That would give you the benefit of being able to charge the X13 from the display, which you wouldn’t get by using a regular HDMI cable as you planned to do, but of course it would also mean you would NOT be charging the MacBook Air while using the X13. I haven’t seen a display capable of charging two laptops simultaneously, maybe due to a combination of relatively low demand and the fact that it would require a larger power supply in the display.

Thanks for clarifying! I won’t be using both laptops at the same time, so I don’t mind using 1 USBC for Mac then unplug, move that to X13 or use HDMI. Then use other port to connect to laptop for keyboard / mouse

@heidibe  If you'll only be using one system at a time and don't need to keep the unused laptop connected to power while you're not using it, then using only the USB-C cable and switching back and forth between systems is the best option.  That way you don't have to worry about having a separate HDMI cable plus another separate USB cable if you want video+USB functionality with the X13 -- and even in that setup you'd still need a separate solution for power on the X13.  But if you just use USB-C, you'll only have a single cable going to your display, and that single cable will carry video, USB data, and power for whatever laptop you're using at the time, so it's simpler and more functional all around.

Sounds perfect! I can get that on 21DE as well yeah? 

@heidibe  Yes indeed!

Big thanks for your help, appreciate it!