The issue I'm experiencing is that I recently upgraded to dual 27" external monitors (Lenovo L27q-30) that support 1440p resolution, but they are only running at 1080p despite installing Lenovo's recommended driver for the new monitors. Whenever I select the 2560x1440 option for the external 27" displays, the screen goes black and periodically flickers. They work just fine at 1080p though. I previously was running dual 24" external monitors (Acer B246HL) through the docking station via DP at 1080p resolution without issue.
I'm using an HP Elitebook 840 G6 notebook (ProdID: 7KK19UT; i5-8365U @1.60 GHz; 16GB RAM) with the HP UltraSlim Docking station (PN: D9Y32UT#ABA), which I believe is also referred to as the 2013 model. I've eliminated the issue being with the cables, the laptop hardware, or the new monitors by isolating the issue to the docking station. I hooked a monitor up directly to my laptop via HDMI (No DP on laptop and no HDMI on docking station...) and I was able to view in WQHD. The laptop is capable of supporting dual WQHD monitors and the docking station is supposed to as well. I'm not sure what the issue could be though. This thread is the closest I've come to an answer, but the links for the firmware downloads don't seem to work for me and I can't find them elsewhere on HP's Software and Driver Downloads page.
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