Solved! XPS 13 9350 doesn't output a resolution higher than 1920x1080, even though 2k monitor is set as 'only screen'

[TechiGamer]

Hi,

For my XPS 13 9350 (1920x1080 resolution version), I bought Dell's USB-C adapter that allows me to connect an external monitor using HDMI.
The purpose of this dongle is to connect the XPS 13 to my 2k Asus monitor over HDMI.
Although I have set '2nd screen only' when "projecting" in Windows 10, I am unable to set the resolution of the output to higher than 1920x1080.

While I understand that this would be the case if we were mirroring the two computers, I believe I should be able to set the resolution to maximum when using my Asus monitor alone, especially given the fact that Intel's Graphics chip that is inside the processor can support a much higher resolution, according to their datasheet.

Any suggestions?

*edit: according to device manager, I have the intel HD graphics 520 chip

 

[webworkings]

You can't set the size to anything higher than the computer is set to allow. No matter the external device. The computer will have a max setting.

 

[Glenwing]

Use a USB-C to DisplayPort adapter, not HDMI, assuming the monitor has DP. Which monitor is it?