Do you mean your cable signals or your DVD is 480i? If it's your cable, then I suspect your cable box needs to be set to output 1080i. Your component cables can handle 1080i--mine do from my Comcast box. But, on my Comcast system, there are TWO versions of channels that offer HD content. For example, there are two CBSs; one in SD, and one in HD. And they're no where near each other on the "dial;" the SD CBS channel is channel 6, and the HD CBS channel is channel 212. Perhaps that's the way it is on your system. If your DVD is displaying 480i, then you need to tell your DVD player to output 480p, or progressive. I had to turn that option on on my DVD player, as that was happening to me, too, on my Vizio 42" LCD (which I love, by the way).