RX580 Overscan Driver Issue

[Byodood]

I upgraded to an RX580 after my computer went thermonuclear a couple months ago, replacing an R9-270x. I use an older Panasonic TV as my monitor. Mainly, because it's large, but also because I already had it. 

 

My R9-270x did not have an issue with the built in overscan correction on the AMD software. I set it to a 5% scale, and it worked perfectly, never had an issue. The problem started when I replaced it the 580. Using the proper driver for the card, I set the scaling to 5% like normally, except now, all my framerates are limited to 30 fps, including all Windows programs, and even the mouse. It's very choppy and laggy. The same thing happened in games, until I put it to fullscreen, and turn off V-Sync. When V-Sync is off, I get the normal fps you'd expect from this card. Turn it on, back to 30 fps. 

 

Now, the question is, how can I fix it for everything else? this happens to videos too, until I make them fullscreen, and in games the screen-tearing is absolutely abysmal. I've attached pictures of an example game, EVE Online, because the FPS counter shows a graph. The one locked to 30fps is with V-Sync on. 

[AbydosOne]

@Byodood Does your monitor/PC have an option to turn off overscan? Usually it will be under a picture setting ("Wide"/"Full"/etc.). What's the exact model?