That looks like a classic indication that the video card my be overheating and/or going bad. If the situation doesn't improve, you'll probably have to replace the card. When a card is going bad or ready to die, the image posted is what you'll usually get.
That said, before replacing the card, make sure you're using the correct display resolution for your monitor. If you're using the correct resolution, and refresh rate (usually 60Hz for LED's), than yeah, it is most likely a bad card. You might also make sure you've got the video card drivers installed, although it still wouldn't display what's being shown in the drivers aren't installed.
Let us know.