Late to the party, but wanted to post what worked for me. Our 6 year old 55" Visio started going black several days ago. It would run fine for 20 or 30inutes and then go black. Turn it off for an hour or so and then back on and same thing.
This TV is mounted above a fireplace. I thought it might be overheating from all the visible dust on the back. We took it down this morning and I blew out all the air vents with my air compressor. Reinstalled TV and it has been running fine now for over 8 hours. Maybe something to try. This TV has always had the picture set to "Vivid".