According to your description, I suggest you refer to the following information:
1. The graphics card switching mode of your machine is a program switching mode (it cannot be switched as a whole) and cannot be changed.
Note: If you need to switch the graphics card, you can right-click on the desktop-select "Configure Interchangeable Graphics Card" and then click Browse in the pop-up interface to select the program to switch, and then click "Power Saving" or "High Performance" (the high performance mode is to use a discrete graphics card; Power saving mode is to use integrated graphics card).
2. Your graphics card problem is related to the driver. It is recommended that you install and use the official driver:
G4-2047tx Graphics Driver
Win7(64-bit):/Chat and consult an online engineer to help you solve the problem further. More product information is available in www.hp.com.cn/800..