My tv comes on for 20 minutes then turns off for 20 minutes

My tv comes on for 20 minutes then turns off for 20 minutes

My tv stays on for around 20 minutes then turns off and wont come back on for 20 minutes I changed two of the boards and still same thing

ANSWERS:

@lcjson you are not giving us a lot of information to work with. You do need to tell us what model this TV is and what boards you replaced as well as why you replaced those. The most common issue the way you describe them is caused by bad capacitors.