TVs are not very good displays for computers. You have to go through a bunch of settings to turn off as much image processing as possible. Even then, the latency will still be higher than a gaming monitor. You have to disable overscan, which always seems to be on by default even though it's only useful for CRTs and makes absolutely no sense for a digital display with digital signals. Also, I've never had a single TV that will actually go into standby when commanded. It will just stay on with a no signal message when the computer turns off the output.

There was a panasonic (I think it was them) that had a Displayport connection, but that didn't last.

I suspect HDMI threatened to cut their licence if they kept putting DP on the TVs.