That's one of the known symptoms that you know to remove from service to get it fixed. If left in service other boards can fail but only a tech can look to see what needs replacement. The cause we know of was only covered on some models but if you left it in service the maker only changed the parts that were covered but outside of that, it would be up to the owner to decide if repair was cost effective.
I read you found the bad caps, but since it remained in service with the bad caps, other boards are now likely dead.
I have a Samsung 32" LCD tv model: LE32R87BDX/XEU that was purchased around 2006/07. It began playing up some time ago, it would take a good while to come on. This gradually became worse, it would make a loud buzzing noise and the picture would be extremely distorted however, if left on the buzzing would stop and the picture would eventually return to normal. This also gradually got worse, the tv took longer and longer before it would start working properly until eventually it just wouldn't turn on at all. The screen remains black and the light on the power button flashes on and off. After reading through forums I found that this model has issues with bad capacitors, I tested all the electrolytic caps on the power board with a multimeter and two appeared to be completely dead. I replaced all 5 caps in that group with ones of a higher voltage value but kept the uf and temperature values the same. The tv still wont power on and the light on the power switch is still blinking. I also checked the internal fuse which is fine. I have read that it may be the power inverter, could anyone tell me if this is correct and if so would I have to replace the whole board or would I be able to just replace the electrolytic caps on there too? Any help would be appreciated