The random lockup of UNxxES7500 through UNxxES8000 LED TVs along with a frozen image resulting in power cycling (the TV turns off and then back on). The symptom can occur anytime after the SMARTV boot up logo
disappears from the screen.
Solution: Replace either SMPS and the cable between the power
supply and main board .
The second possibility is the LVDS cable and T-con, although this is more likely to occur only on early production TV’s.
Also: Check SMPS cable connector for discoloration it will appear as a slight, brownish color centered around the 5VDC pins on either the connector or plug. If this discoloration is visible, replace both the cable and the SMPS.