I have a Dell Inspiron N7110. When I boot it the display lights up (ie the backlight) but there is no data or images. If I then plug in an external monitor the boot screen for Windows 7 shows on the external device and it works fine, but the laptop display just goes dark as soon as I plug in the external display. If I reboot with the external display connected neither display come on (the laptop display backlight comes on), but if I disconnect the external display and reconnect it, the external display then shows the normal boot screens and Windows 7 etc. I've tried a different panel in the laptop with the same result. The cable to the display looks good. Is there a chance that it could be to do with detecting the lid being open or closed? Can't find a switch for this. Any ideas would be greatly appreciated.