If you have attached your monitor to your video card using a DVI cable, the OSD menu adjustments will, in fact, be unavailable to you, except, in some cases, for the Brightness control and, less frequently, the Contrast control.
OSD menu functions can only adjust analog signals from a video card. The DVI signal is digital. Consequently, the OSD menu is incapable of adjusting the DVI signal and most of it will be inaccessible. The Brightness control is the occasional exception because it adjusts the intensity of the monitor backlights, which can function independently of any signal from your video card, analog or digital.
With that said, you should still be able to adjust the picture on your monitor through the driver software provided with your graphics card.