Screen or IC Chip problem?

One day, my screen went black suddenly. I could see the backlight was on.

I took off the screen and put it in another phone and was still black.

I ordered another screen and the screen came on but without touchscreen capabilities.

I put the old screen back on and it was still black.

While doing a hard reset, a slapped it against my palm and the screen flickered and came back on.

Since then, It's blacked out a couple times, but flickers back on when I bang it like a TV set from 1960.

Any ideas as to the cause?

Thanks for the help!