I totally agree with what Dave said about the video cables. I've seen all sorts, and dissected many over the years. I can usually tell just by looking at them, which ones are "good." The nice skinny, highly flexible ones tend to be the worst - the wiring is often just straight through, with not even twisted pairs for the RGBS signals. The good ones are much fatter and not so flexible, due to having actual individual coax lines for the video signals, and usually heavier outer shielding braid. They often have common-mode chokes molded right onto the cable, or tightly attached.
The skinny ones were just about adequate for VGA in the old days, but if used for more modern, higher resolution monitors, the video performance limits are obvious, and it's safe to say the EMC is much worse too.
Ed
