Can I mount wall 75 inches (50kg) tv on plasterboard?
To answer the question I would say don't do it. But an easy solution is to determine the width of the studs in your wall and then get 3/4" plywood and cut a rectangular panel long enough so that you can securely fasten both ends into a stud inside the wall. Then you can securely attach your TV bracket into the 3/4" plywood and it should hold up well. Once I actually had 2x4's and cut them to be 17" long. I used 3" screws to secure them horizontally onto the wall attaching them to the studs that were spaced 16" in the wall. I made sure the horizontal studs were placed so that the screw holes of the TV bracket were centered in the horizontal studs I attached to the wall. If you do this correctly your TV is not going anywhere. This makes your television stick out a couple more inches but if you don't mind this you will have a very securely connected TV to your wall. Good luck!