several things to check when looking at HDMI. (I'm a jack of trades installed and setup these when they first came out)
Direction, Some cables are direction sensitive they have big arrows on them these usually are the cheaper cables.
Full wired cables, just like with SCART you have Half and Full wired cables. (You can check this with a multi meter, Chinese made cables tend to show this disturbing anti-feature)
Resolution, TV's in general doesn't like anything outside their native resolution, some cheaper TV's do not properly send their preferred resolution over HDMI.
Shielded cable, I have yet to see a unshielded HDMI cable but I wouldn't count those out.
Don't use a DVI to HDMI for a TV it just doesn't give the desired result 9 out of 10 cases.
It is late i just had a 16 hour day and I've drank a little Chuck and Patcc know how this affects my thinking patterns in an interesting manner.