I know there are those who think cabling really doesn't make much of difference if any in audio. Fewer still seem to consider they make any difference in video from my readings in the web. But. . . my personal experience is that they can and do make a difference. And in the case of video, it's a VISIBLE difference, which leaves less to the "imagination" or fewer claims of placebo "effect." (Well maybe, people who believe it is all placebo seem to hold with that mindset).
I've been using pretty good cables for the video aspect of my system. I started out with a "no frills" version of an Audioquest HDMI cable, silver plated copper, and it really was a step up from a plain jane HDMI cable. I was very happy with this cable, but when I bought my PS Audio PerfectWave DAC and Transport the dealer was blowing out top of the line PS Audio HDMI cables and I bought one to try in place of that Audioquest (the conductors are all silver). WOW. I am under the impression that it took some time (really a month or more) to fully break-in, but when it did, wow, just amazing picture from DVD and Blu-ray. Vibrant, detailed, very watchable.

Shortly after I got cable the HDMI went out on my DVR unit, and I had to use component video cables to connect to the TV. I used a "no frills" Audioquest that was similar to the HDMI, silver plated copper, and it gave a really good image, detailed, vibrant, warm. Recently I saw that someone was selling top of the line Audioquest all silver component cables at literally one/nineth of their original cost on ebay and bought one. Wow. A surprising upgrade in picture quality, everything was both a bit more detailed AND a bit mellower looking. I thought this was money well spent, and not that much in "audiophile" terms.
I got to looking at that plain coaxial cable the cable company has coming out of the wall and decided to look about for an inexpensive upgrade. I found a used cable company online selling a Tara Labs "RSC Vector One" coaxial cable for thirty bucks and decided to give that a try. I was really surprised at the improvement that made to the TV picture. I had to totally readjust my settings several times over the first week as it broke-in I guess, but right now I have a broadcast tv picture that I just marvel at. In a way it makes sense, as this length of wire from the wall to the DVR should be an important link in the digital chain. I just wish I'd thought to replace that length of cable much earlier. I thought I had a really good tv before (40" Sony LED that cost about 1200 bucks) but now it's as if I spent more on the top of the line model in this series. HDTV is even more three dimensional now. And I believe that the audio (I use a glass Toslink digital cable to route the audio to my DAC) is improved a bit as well. Very happy!
Ever since I bought the tv, and with its predecessor as well, I've been using the best power cables I can afford on the
tv as I believe that is a contributing factor. Right now I'm using a PS Audio xStream Premier SC that I got a great deal on used, and it really is doing its part to deliver this great image to my eyes.
I'd encourage anyone who hasn't experimented with cabling for video to give it a shot if they believe in cabling and have fun trying cables. And if anyone has done some experimenting I'd love to read of their experiences.