HP Pavilion Dv6000 with Vista screen goes blank

Question

I have had this computer for about 1 month now. It works fine most days but randomly the screen will go blank totally black or it will turn into a white screen with blue zig zag lines (looks like the twilight zone) going through the sceen. Once I hit the power button the screen goes black and if i hit it again everything comes back. the computer does not shut down or anything. As a matter of fact once the screen goes out i can still type, i just can't see it. thank you