Horrizontal Rolling with ATI+Component adapter

[GreggWG]

Ok I finally got my HTPC completely built, even inbetween moving, and I'm about to install SageTV. The only problem I have is a rolling effect going up the screen on the TV. Its most noticable on a black background as a slightly purple discoloration that slowly creeps up the screen. I have the exact same problem on both my primary computer which is using WinXP Pro and a 9800XT and my HTPC which is using Win2K and a 9800 Pro. I've tried powerstrip but there isn't a set of options that gets rid of this rolling, is there something I'm missing, or is this the nature of the beast?

[mls]

Is it a horizontal bar that is slowly moving up the screen? If so, you probably have what is called a "ground loop" problem. What happens there is some stray 60Hz power line frequency gets into the signal (usually from multiple ground connections in the wiring and cables). Since NTSC TV has a vertical scan rate of about 59.97Hz, the extra 60Hz that snuck into the signal produces a slowly upward moving horizontal bar.

Ground loop problems, especially with video can be very hard to track down or elimate. There are a few ground loop breaking adapters available, however you'll probably have to do some Google searching to find out more details about how to track down and/or elimate it in your specific situation.

I've had a ground loop problem for some time myself that I have never totally managed to elimate, but have at least found a way to reduce it to a level that is barely noticable.

For audio, a ground loop can produce a steady, or sometimes slightly varying 60Hz hum. Solving the problem with audio is usually a lot easier than with video though.

I wish you luck since ground loops can be very difficult to deal with for video.

[GreggWG]

Reading the articles I've found online this seems to be the issue, this would also explain a slight audio hum that before now I thought was just normal, this is certainly discouraging, but I'm sure I'll figure out a way to work through it. Thanks for the help!