This might be a known problem. Ask Samsung for a one time free repair. Why? link follows.
When I turn the TV on I get a snowy green screen with vertical lines. Then it shuts itself off and on several times before I get a good picture. Also does it using different input sources. I've tried different cable boxes, same problem. What is the most likely cause, can I DIY it, and what would be a reasonable cost to have it repaired? Thanks for the help.