Hold the power button on the TV panel or remote and plug in the power cord.
The (often identified as TP.MS338.PB801) is a widely used universal smart Android motherboard for LED/LCD televisions. The specific firmware version you are looking for— 1366x768 resolution, 512M RAM, Ref60 —is a system file used to either restore a bricked device or update the display configuration. Hardware & Software Specifications Download MS338 PB801 1366x768 512M Ref60 part5 rar
Varies by firmware; your version is specifically configured for HD Ready (1366x768) displays. Download & File Structure Hold the power button on the TV panel