Sagetv Media Center Why Is Cable TV On My Computer Is Fuzzy?

Why is Cable TV on my computer is fuzzy? - sagetv media center

I already have many TV tuner cards, and all have the same result. I open Windows Media Center, SageTV cover all TV stations, and the picture is very confused. Is there a solution for this? No tuner card, as I had replaced, I have also tried digital cable, without success. The image is perfect cable on my Sylvania 20-inch CRT TV. Ideas?