Hi everyone,

On my Windows 11 machine (HP EliteBook 850 G7) I previously had two 1920x1200 displays, and all was well. They have both recently failed, being around 15 years old, and have been replaced with one 1920x1080 and one 2560x1440. I'm struggling to make them both work at full resolution.

• Both displays are connected via an HP G5 dock, which claims to support two displays at "QHD" (I believe this is 2560x1440) under DisplayPort 1.2, or three at 1.3 or higher. I can't find any information about the laptop's DisplayPort version, but I'd imagine that it's at least 1.2.
• With both connected to the dock with DisplayPort, they both run at 1920x1080 and Windows doesn't show a 2560x1440 option (it does have a rather strange 1280x1440 option though).
• If I disconnect the smaller one, then 2560x1440 shows up and works correctly.
• If I connect the small one again, then the larger one drops back down to 1920x1080.
• The specs for the laptop say nothing more than "Supports resolutions up to 4K at 60 Hz via DisplayPort".
• The specs for the i7-10710U CPU say that resolutions up to 4096x2304 are supported, with up to three displays.
• I also tried using HDMI instead of DisplayPort: connecting the larger display to the dock resulted in the same issues as with DisplayPort. Connecting it to the laptop's own HDMI port resulted in it disabling the smaller screen (which was still connected to the dock). I'm not familiar enough with Windows to figure out how to enable it again - can anyone help there?
• I don't use the laptop's built-in screen at all, and have the lid closed during normal operation.
• I've updated the Intel GPU drivers to the latest version.

Any ideas what's going wrong here and what else I could try?