Any of the analog monitor outputs will suffice if all you are looking for is the on-screen menu: s-video, composite video, or component video. I use component video because I have a couple of analog video sources (one connected via component and one via composite) so I need the component anyway. If you have no analog video connections to the 990, then you can use whatever's handiest. A cheap composite video cable would suffice for the OSD (like the skinny cable with yellow connectors that probably came with your Denon).