I have a Probook 430 G6 and I connect it to a Thunderbolt 120W G2 dock when I'm @office with an HP 1440p 27" monitor on a DP port. Recently I needed more desktop space and so I took an equal second monitor (1440p) and I connected it to the second DP port on the dock. I can get only one monitor @1440p and the other one is limited to fullHD resolution (1920x1080). I tried to use a USB-C to HDMI cable connected to Thunderbolt port on the dock but it doesn't change. I was able to get both monitors @1440p connecting one of them to the HDMI port on my 430g6 directly and leaving the other one on the dock.
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