970 GPU, Little window in the top left of display

[xmagicwafflex]

So my GPU is a gtx 970, I have a 4k monitor. There is a little window in the top left that is not visible but my mouse can go there. Here is a picture of my desktop http://i.imgur.com/Y8NRSVx.jpg It gets very annoying and would like to have assistance to get rid of this. Thanks

 

[cst1992]

I don't get it. You have a 4096x2160 monitor, and the image you provided is 4864x2160. So the window occupies 768 additional pixels?
This is a print screen? Shouldn't the desktop show the 4096x2160 image on the right?