[NAME]  Thanks for the kind words!  It's always nice to hear that my posts have helped people beyond the person I was originally replying to.It does indeed sound like you don't have Thunderbolt if the TB16 doesn't work at all, since it requires TB.  The WD19TBS has a newer chipset that is backward compatible with USB-C, but only at reduced functionality, so in that mode it would like a regular WD19, which with your system would be just like the WD15.In terms of your question, if you disconnect your 1080p display, you should be able to run 5120x1440 30 Hz through the WD15 because your laptop and a WD15 would be able to run a single display at 2560x1440 60 Hz, and those two setups should be identical from a bandwidth standpoint.  But I say "should" because not everything that SHOULD work in the tech world always DOES work.  (That reality is one element of what keeps me so busy here -- particularly as these type of scenarios crop even when using Dell systems with Dell docks/displays, where something that should work doesn't.)  And then at that point if the extra display real estate was worth the extra cable, you could connect your 1080p display via the built-in HDMI output, since that output would certainly have enough bandwidth for 1080p 60 Hz.  I see that you're currently using VGA for that display, but if the display happens to have a DVI input, you could get an HDMI to DVI cable or adapter to make that work, and you'll even get superior image quality as a result since VGA is an ancient analog-based signal, whereas everything else is digital.  So that may actually be worth considering even if you don't rework the rest of your setup.But 5120x1440 even at 30 Hz won't work if you've also got a 1080p 60 Hz display drawing bandwidth.  The total bandwidth requirements for that setup are just slightly above what's available over the USB-C link.Good luck!
Help! I have a Dell Latitude 5480 laptop and a WD15 docking station. On Black Friday, I took the plunge and bought a Samsung G9 49" ultrawide monitor with 5120x1440 resolution. I cannot get the new monitor set up with 5120x1440 resolution when it is connected through the WD15 dock. I can only get the 5120x1440 resolution to take effect when I bypass the dock and plug the monitor directly into the HDMI output on the laptop. Is there anyway that this combination of laptop and dock can achieve 5120x1440 while incorporating the HDMI output on the dock instead? I also am running a 1920x1080p monitor with VGA connection set up through the WD15 dock. Any advice would be greatly appreciated! Thanks!
Latitude 5480, WD15, Samsung monitor no 5120x1440