Can't use dedicated GPU on dual monitor setup

Question

I have a DELL Precision 5520 notebook with an integrated Intel(R) HD Graphics 530 GPU and a dedicated Nvidia Quadro M1200 GPU and I have two screens through a DELL WD19S docking station, both screens connected via display port. I'm trying to force my Windows to use the dedicated GPU for everything, including the windows desktop environment cause it looks like the integrated GPU can't handle more than 1080p but my dedicated GPU can go with even 4k when I'm playing games. My problem is that no matter what I try, Windows won't use my dedicated GPU for the desktop environment, only for games. Here's what I've tried so far:

1. Updating windows
2. Updating all drivers with DELL support assist
3. Updating both GPU drivers from the manufacturers' websites
4. Installing a previous vesrion the nvidia driver (then went back to the latest)
5. Disabling integrated GPU completely (this way my dedicated GPU saw only one screen)
6. Forcing the use of dedicated GPU from Nvidia control panel (here I can see both screens attached to the integrated GPU despite dedicated GPU being forced from the settings)
7. Restarted my notebook after every single change or update I've tried just to make sure
8. Tried forcing dedicated GPU from BIOS but there was no such setting there
9. Maxed out everything in power settings from the control panel, nvidia control panel and BIOS too and I'm plugged in, I'm not on battery

All my video games run on the dedicated GPU, there is no problem with that part, they run perfectly. But I'm using two screens through a DELL WD19S docking station and I need both screens to run at 4K or at least 2K. My previous notebook that didn't even had a dedicated GPU could do that easily so I'm sure there's a way to do it with a Nvidia GPU. I know I'm missing something but I can't figure it out.

Answer 1

Hello

Thank you for your question and reaching out.

Most of Troubleshoot have been done by you already, really appreciated.

Did you try to Contact to Dell support if the actual Motherboard or GPU support dedicated GPU or not ?

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