Screen Tearing but only partial.

So, I just logged back in after playing a few dungeons earlier on in the day, and notice that for some reason I now have pretty intense screen tearing. The thing is...it's only in the top quarter of the screen. The rest is completely fine, but the top of the screen has extreme screen tearing at the slightest movement of the camera. Before now, I had no screen tearing whatsoever playing in windowed borderless w/ 60fps cap.

I tried switching to fullscreen but that didn't fix it. Exiting and re-entering the game didn't either. Any suggestions?

Edit: Tried enabling v-sync/triple buffering via the n-vidia control panel, and while it worked for fullscreen, it won't for borderless windowed. Is there a way to fix it on that setting?

Edit 2: Found the problem. Computer is labelling my TV as my #1 monitor and my actual monitor as #2 for some strange reason, and that was causing the screen tearing.