Laptop resolution on external monitor?
Solution 1:
If you attempt to clone the laptop screen to the external monitor, you will only get 1366x766, however, if you use the external monitor as either extend or as the only monitor, you will get 1920x1080.
Please note that the laptop screen resolution should be in the specifications when you buy it - unlike CRT monitors, flat panels are made up of a set amount of pixels and whilst you can choose a lesser total and "stretch" (or letterbox), you can never go bigger than the total (excluding on a few graphics cards which allow panning - but this is rare now).