I would say it's the LCD that is faulty already but do try these steps just to make sure it's the actual graphics card that has the problem.
- First, connect and external monitor and see if the same problem will persist. If it doesn't persist with the seconds monitor that means it's just the built in display that has the problem but if the same issue will happen with the external monitor that means it's the graphics card.
- Another step you can try if it's the built in display that has a problem is to check the connection of it from the motherboard, make sure it's cable is seated properly.
- If these will not work the only way to solve that problem is to replace the screen itself.