Why Does the Pen Display Have Black Borders and Cannot Be Displayed in Full Screen After Connecting to the Computer?

In general, the reasons for the black border on the Pen Display or the pen display cannot be displayed in full screen are as follows:

  1. When the computer was equipped with a graphics card, the connection cable between the pen display and the computer monitor is not connected to the graphics card.

  2. The computer display resolution is not uniformly set to Best for HAT.

 

How to solve the problem that the pen display has a black border and cannot be displayed in full size?

 

Solutions for macOS

   1. Make sure the Pen Display connected with the computer running Mac System.

   2. Open the System Preferences on Mac and find the Displays.

       

    3. Select Best for HAT in optimize for both Displays.

 

 

 

Solution for Windows

   1. To ensure that the image shown on the screen of pen display is the same as that of the computer screen, please plug the connection cable between the pen display and the computer to the integrated graphics card or discrete graphics card. (P.S. please plug the cable to the discrete graphics card but if the computer without a discrete graphics card, please connect the cable to the integrated graphics card.)

    2. Right click on the desktop and then select Display settings.

                                                                                                                                                                   

       3.  Click on Display 1 and select the recommended resolution of the system, it is shown as the picture below 

     4. Click on Display 2, select the recommended resolution of the system, it is shown as the picture below

 

 

If the above-mentioned methods cannot work, please check if the driver of the graphics card is installed, if the resolution of the pen display can be recognized or not, and etc.