, when the problem is a power board, backlight, HDMI port or software issue and the TV still looks great. It is usually better to replace it when the panel is broken, parts are scarce, or the quote crosses 40 to 50 percent of a new TV's price. You get less stress and better reliability. The quickest next step: get a written repair estimate, compare it with a new TV you would genuinely buy, and apply the 40% rule. Once you see the numbers, the decision is usually obvious.