I have a similar problem with a distorted, pixelated picture. The problem is that a hair managed to sneak it's way into the connector and then snapped off when I tried to remove it. I have yet to open mine up and repair it, but I think it will be relatively simple when I find the hair node.
The important thing is to troubleshoot. If you think it's the connector or cable, try using the coaxial output. If it doesn't power up, you have other problems. Start at the easiest to replace - not the likely culprit.