I have a 19" LCD monitor (LG FLATRON Wide).I have got an NVidia graphics card too (256 MB).It's been almost an year without any problems, but now I need some help. What I am seeing are some horizontal lines moving from top to bottom.When I change the screen refresh rate from 60Hz to 70Hz, the problem gets solved but then I start seeing some shadow to the right side of everything (text/icons/menus/cursor etc.) on screen.When I change the resolution, the picture gets worse. I have tried re-installation of the graphics card drivers without any success. Any sort of help would be appreciated.
I think this problem is related to your LCD. Try plugging a new Monitor and see if problem persists or not.
Since changing the resolution solves your problem.I feel it as a Graphic card issue. Try using a different graphic card if the problem still persists then try replacing your Monitor. I'm sure in one way or other your problem will get solved.
Try to solve your problem by removing the graphics card and cleaning if the problem is not solved by that plug in a different Monitor and see if the problem is solved or not. If the problem still remains then consult some technical guys.....