I just bought a new Dell Inspiron pre-installed with Ubuntu 11.10. All was fine until I updated the OS. Since then, I have this flickering line at the top of my screen and it won't go after rebooting or changing the screen resolution. It gets really annoying. I don't know which update did this. I tried reinstalling the image from Dell, and it worked fine until I applied the updates. I tried to take a screen shot but it does not show. The line seems to be outside the desktop area. Help please... Thanks!