@harjotsing77920 your description is a bit confusing. Are you saying that the TV turns on but shows lines (horizontal or vertical?) for 5 min. Then the lines clear up and you have a normal picture. After an additional 2 minutes the TV freezes but displays a normal image?
If that is sothen this could be a bad mainboard (GPU and memory issues) as well as a bad T-con board. Of course, there is always the chance that this is even a bad display panel.
We will need to know the exact model number for your TV. Then remove the back cover after unplugging it. Now take some well focused images of all of your boards. Post those with your Question. That will help us to see what you see. It may also help us to further troubleshoot your TV.
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