This issue will occur on any NVIDIA Optimus-based ThinkPad where there is an external display connected to the ThinkPad and the user wants to control the display mode through the Microsoft Windows 7 operating system method (FN + F7 or "Windows Key" + "P") and it does not appear to be successful.
The following ThinkPad system running Windows 7 configured may be affected by this symptom:
To adjust the displays connected to the ThinkPad with NVIDIA Optimus, the user should utilize the NVIDIA graphics control panel.
These systems have two Graphics processors. One is called a Discrete Graphic processor and the other is called an Integrated Graphics processor. These processors are working together to control the graphic information and the display or displays being utilized which in this case is both the LCD and at least one external display. Some ThinkPads with NVIDIA Optimus can support more than one external display. Because this is a highly complex graphic system utilizing both graphic processors and displays the operating system, Microsoft Windows 7 is not aware of how NVIDIA Optimus is controlling the external display or displays and the LCD monitor. Microsoft Windows 7 operating system is unaware of the NVIDIA Optimus controls for displays.