My lap top screen won't work

Hello,

we recently bought a hp laptop, it was working fine right upto the other day and then all of a sudden the screen went odd and flashed black and went back to normal then did the same thing again, we ran the cc(?) cleaner and our AVG scan, there didnt seem to be a virus and now when we try to turn it on the screen will orginally start up, make the on noise up, flash the menu that you have to push esc for and turn black again , it flashes real quick , then sometimes, you can see it try go to the sign in board but it does the same thing, has anyone got any suggestions to help us

Thanks