I have a dual monitor setup, an ultrawide 3440x1440, and just upgraded my 27" 1440p to a 32" 4K (Gigabyte M32U) in a portrait orientation.

The 4K monitor has PBP and PIP capabilities. My gaming PC is working fine with the secondary 4K monitor using PBP, with a resolution of 2160x1920 and properly filling the space. However, on my work PC the 2nd monitor is also at 2160x1920 in the proper orientation, and it only fills up the center (I'm guessing roughly 1/4 of the available screen.)

It makes me think that the resolution is correct, just not scaling to use the space.

Any idea on how to get my work pc to properly fit the space?

And it just started to randomly work. Nevermind!