The answer is on page 15 of your instruction manual. Remember that, for video, DVI and HDMI are synonymous. There is a small DVI button on the front panel of your unit next to the pause button. That button should have various DVI settings--you are probably set on "off" which is why you get no picture. You need to hit it sequentially until you get to 720p or 1080i whichever you prefer. I use my denon 5900 with both component connections (connected to a separate video input) and the DVI connection because my Sony HDTV locks me out of picture size adjustment (normal, full, zoom, wide zoom) when in the DVI (or HDMI) mode, but not when in component mode. So, for some DVDs, especially for home photos, I use the component hook-up so that the Sony TV doesn"t "automatically" distort my images. For Denon products, turning the DVI mode to "off" automatically switches it to component output. My main gripe with Denon is that you have to switch the DVI on or off from the front panel and not from the remote. Go figure. I guess DVI or HDMI was an afterthought for them.
