Bought this 21" RK3399 Android wall-mount touch screen last year from someone in China. Worked fine for several months hanging on the wall, displaying streaming videos 12 hours a day (must have been hard job for it I admit).

One day it just abruptly turned off while working, and it won't start up ever since. Sending it back to China for warranty repairs and back is obviously uneconomical.

This is how it looks inside, no visible damage, no popped capacitors etc.:

Any ideas what could have died in it? Power supply is okay.

Would these parts be of any interest to anyone if I try to sell them?