My laptop screen display was appearing white alongwith lines. I changed the screen connector cable but the problem was not resolved. I also changed the sceen but problem was still there. Finally, all screws of laptop casing were opened to investigate the route cause. On removing all the screws, the screen display became normal. Now screws were fitted one by one to find problematic screw. It was found that the screw that tighten the screen hinge with laptop motherboard casing was causing problem. When it was removed/ loosen then screen display became normal. Basically this screw was causing short circuiting of motherboard due to which screen display was getting white.
I hope that other users may get some idea from resolution of my white laptop screen problem.