Screen shows gray lines
Hi, I've got two gray horizontal dot lines up screen (in the status bar area) and some weeks later a new one, this time vertical in the middle of the screen.
When connecting to a big screen, such as a LG LED TV on the thunderbolt port > HDMI, the lines doesn't appear.
Is this a LCD screen problem? Or could be on the graphics card?
Can someone give me some information about it?