Resolved Weird Box on screen after install - No idea what to search for to get help!

[BandogMusic]

I just installed OSX 10.13.6 and now I get this weird box. It moves with my curser when I get to the boundary.

Can anyone help?

Screen capture of the box moving with cursor:

 

[BandogMusic]

I upgraded in advance of installing a new video card... I've never seen this issue... please help!

Thanks guys.

 

[BandogMusic]

Another forum pointed me to the Zoom settings... I toggled a couple options and that made the box go away.