I don't know how I managed this one, but all the desktop is on it's side. What is supposed to be on top is on the side. As I write this, the message appears vertical. I have to physically turn my laptop so that I can read anything on it. Since I have no clue how I did this; I have no clue on how to correct it.
Open Control Panel>Display>Settings tab>advanced, navigate through the tabs to find a rotate display option.This option has come due to the graphic card you have installed. The option should allow you to rotate the display back to its original orientation.
If you have Nvidia software installed,then look for NVRotate;with NVRotate, you can rotate any display 90, 180 or 270 degrees.
You may also try Ctrl + Alt + Up/Down arrow. [hot keys]