Got the same thing going on with mine. It seems to be the digital board. Apparently, the DNIe chip gets loose after a while and causes the green bars. Hundreds if not thousands of these sets have the same problem. There are 3 fixes: one, you can apply pressure to the DNIe chip by creating a homemade "contraption" using nuts and bolts, but this seems to last a few weeks at best. Two, you can contact JD Electronics (
http://jdelectronicsinc.com/) and they will attempt to fix it by "reflowing" the DNIe chip for $40 and return shipping. This seems to work for most people. Three, you can write to the New Jersey Attorney General (follow the information on
http://forums.cnet.com/5208-13973_102-0 ... w;forums06) and a lot of people actually had Samsung repair their sets for just labor or for free. Hope this helps, just been going through the same thing myself and looking through tons of websites!
Scott