The ornamental design for a portion of a display with a graphicaluserinterface, as shown and described.
FIG. 1 is a face view of a portion of a display with a graphical user interface, showing my new design, according to a first embodiment of the design; and,
FIG. 2 is a face view of a portion of the display with the graphical user interface, showing my new design, according to a second embodiment of the design.
The broken lines showing of the device is included for the purpose of illustrating environmental structure and the broken line showing of the display and portion of the graphical user interface is included for the purpose of illustrating portions of the article; the broken lines form no part of the claimed design.