First of all, Hello everyone, I'm new here. Purchased the Sony 51" Widescreen, KP-51WS510, a few weeks ago and absolutely love it. Also, got my HDTV box from Comcast and WOW, I'm truly blown away. I purchased a DVI cable from Circuit City and was told that it would work. When I plugged it into my HDTV box, I got no picture at all. Component, which is what I'm using, the Monster3, works fine. I look in the HDTV manual and see that I need a DVI-D Dual Link cable. The packaging on the cable says DVI Single Link. It was the Monster DVI400. Did I do something wrong with the cable? Does the DVI cable only work with HDTV channels and not regular? Is there a noticeable difference between the high end Monster3 Component cable that I'm using and the DVI?