There was a HUGE thread about this issue across their entire line of televisions. Many of us wrote to the BBB in Trenton, NJ. Suddenly, the thread is totally gone.
The common problems in this forum as well as others is the tv will not turn on, cycles on and off, takes a long time to turn on or the blue led and red power light flash simultaneously and sometimes will turn on if you wait long enough. Well, mine was the last problem mentioned. It died after the second time around. If any of these happen to your tv but you get lucky and it turns on DO NOT turn it off until you either fix it yourself or pay to get it fixed. More often than not it's the power supply gone bad. On top of that it's usually a couple small transistors on the board gone kaput. They are very easy to replace if you know how to use soldering iron. Spotting the dead ones are even easier. There are how-to videos all over youtube. If you don't know how to replace the transistors you can buy a new power supply for about $100 online. I had a hard time getting Samsung to send someone to fix it because they said it was out of warranty. I had a free 3 month extension because I registered it online. I had to fax them a copy of the receipt and that took them 2 days to attach to my ticket. This will be the last Samsung product I ever buy because their customer service is the worst I've ever had to deal with and I don't trust their products anymore. BTW, the tech who replaced the power supply wouldn't give me a receipt when I asked for one as proof he did the work. He said everything was kept in their computer.