During my Hopper install things were going well and I had only the HDMI hooked up. Video was showing. Then there was a reset where I wasn't getting any video. Something about it not being able to see the TV or something (I go through a Receiver). Turns out we had to connect the RCA cables to get video. When we got through the setup and picked the resolution we could go back to HDMI. Just an FYI if you run into this.