problem with TV display...

I had an older AIW Radeon card and when I displayed my computer on the
TV I get these grey scrolling bars that are easy to see when the
screen is dark. At first I thought it was my TV, or possibly the
cable reception. Then I got a new TV and it has the same problem and
when I plugged the old TV up with out the PC the lines were gone.

So when I got the new TV I did not plug my cable into the AIW card and
I still get the grey bars when the PC is diplyed on the TV. I also
switched from using the RCA plug to carry the signal to the TV to
using the SVideo cable, since my new TV has that plug. Convinced that
it was my old card I bought a brand new 9200 AIW Card...lo and behold
I still have the scrolling lines. Does anybody no what the cause of
these lines are, and maybe how to get rid of them.

Thanks