Laptop screen flickering

Hello,

My laptop screen has started flickering from few days . The title bar and the pointer blink and freeze continuously. It is really hard to write something as pointer freezes. When i select something and try to write the pointer goes on and off continuously.
Do I need a format(as I haven't formatted since i have bought the laptop) or reinstall the drivers?
Please help with this. I do all my studies in laptop and it has been really a problem since it has started flickering.
model-Dell Vostro 2520