Precision 5550 with WD19S docking can't drive two 1440p monitors

Hi,

I upgraded my old 1080 monitors for 1440 monitors. But only one runs at 1440, the other at a bizarre 1920x1200.  I can't set it to any higher.

Docking is on 180W power supply. Updated everything. Windows. PC BIOS, video card drivers, Docking BIOS.

I tried running both screens with Display Port. No luck. Tried one Display Port, one HDMI, no luck. Both are running 60Hz, HDR disabled. If I connect the low res screen alone, it runs 1440p just fine. Btw, they are ASUS 27" TUF VG27AQ3A. They are gaming screens with very high refresh rates, but I have set them to 60Hz. I chose them for cost reason. I think the problem has nothing to do with the screens themselves.

Some guide suggested going into regedit

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e968-e325-11ce-bfc1-08002be10318}\0000

Also 0001 and 002 - and setting the DPMstDscDisable D-Word to 0. Others suggested set to 2. I tried both, Currently on 2. No luck. This should be Display Stream Compression. I don't know anything about it. I guess it's some method for sacrificing visual quality to preserve data bandwidth, so you can achieve high resolutions. But it had no effect.

The docking should manage multiple 4k screens. The laptop video card (intel HD 620) should also handle multiple 4k screens.

My company IT support (external) can't figure it out.

Does anybody have any advice? I'm going a little crazy.

But the funny thing is, because of the high res, I have only like 20% less workspace on one single screen than I did on both screens before ;)