Okay so I tried 3.3v to the pin with no success. Screen did not turn on. 5v to the pin works. I have attached the picture to show that this has worked for me too.

I also have this board. When I connect 12v to the input and probe with voltmeter I only get 3.3v at this pin shown in the pictures above. did any of you test before connecting 5v? I just want to know if its safe for 5v or if I should connect 3.3v from the pi.