-These models are know to have bad OLED Panels, one way you can test the OLED panel is to remove the FFC/LVDS cable that goes from the mainboard to the Tconn, then try to turn it on. If The TV comes on (you will not have a picture, power supply voltages will come up, you might have some sound when navigating the menu, you might see the optical out LED is on) the problem is your OLED panel. If this occurs your power supply is good!

-These models can also have a bad mainboard, test power supply thoroughly before you order.