Dell E171FP - dark 1/3 inch black/dark spot on top

[korotoyo]

I've got a 17 inch Dell E171FP LCD monitor with dark spot across the top of the screen. It's also visible when the monitor is unplugged and powered off. I'm guessing it's a problem with the LCD? Is it fixable or need to be replaced? I have two of these LCD monitors that I'm not using anymore. I just thought maybe if I can fix it before selling.

Please attach picture.