Video (Overlay) and Desktop are rendered apart from each other there are specific controls in the Nvidia control panel for the video surface (also the 16-235 TV scale,or 0-255 modes PC Scale) else use the Application provided ones or use a renderer with specific color calibration capabilities like MadVR
https://forum.doom9.org/showthread.php?t=146228 though you wont be able to use that with PowerDVD only a few players support it so far.
You can also use it commercially for no license fee so presentation systems would be allowed in the public (show rooms,conferences, CES, NAB, Emmys, Oscars, TED, your monthly town hall meetings with it