Resolution of external monitors is lower when Asus ZenBook Lid is closed................

[BedtimeGuy]

Hello! I have an Asus ZenBook Pro Duo UX581LV (the one with the secondary screen built in), and I'm having some issues with external monitors. I have a thunderbolt dock with 2 HDMI ports, and I'd like to plug it in to extend the desktop to two 1440p displays. I don't need either of the built in screens to be on when doing so, as the laptop lid will be closed.

Oddly, the second monitor is locked into only a few very low resolutions (that don't even scale properly with it) when I have the lid of the laptop closed. When the lid is open, I can actually get full resolution on the second display, and something workable (albeit very flicker) on the first display by duplicating the built in main display.


Really not sure what's going on here. I have set the "When I close the lid" setting in windows to "Do nothing". It's worth noting that I get a better result by plugging the second monitor in separately via the laptop's HDMI port, but that defeats the point of having a thunderbolt dock. According the this laptop's specs, it seems like this SHOULD work.Lid closed, 2nd screen locked to low resLid Open, decent resolutions but blurry/flickering left screen

[Falcon_ASUS]

@BedtimeGuy 
Since you mentioned encountering screen flickering issues, we suggest you first check if the flickering occurs when you connect a single display directly without using the Thunderbolt dock. If the flickering does not occur, it is likely that the issue is due to compatibility problems with the Thunderbolt dock.

Additionally, we recommend ensuring that the graphics card drivers and system version are both updated to the latest versions. Thank you.

[BedtimeGuy]

Yes, I've checked and the drivers are up to date (even uninstalled and reinstalled them to be sure). The flickering only happens when mirroring the main display of the laptop to an external monitor. I think it's because the native resolutions are incompatible (2560x1440 for the external, 3840x2160 for the built-in one).
In any case, my goal isn't to mirror the displays, but have the external monitors work with the laptop lid closed (and the two built in displays off).
It seems like the dock works fine with a single monitor at a time.