The ornamental design for a displaypanel of a programmed computer system with a graphicaluserinterface, as shown and described.
The FIGURE is a front view of a display panel of a programmed computer system with a graphical user interface, showing my new design.
The outermost broken-line rectangle illustrates the display panel and forms no part of the claimed design. The remaining broken lines illustrate portions of a graphical user interface and form no part of the claimed design.