My screen will not respond to my touch

My Samsung Galaxy s-3 sgh-I747 touch screen is not responding. I have rebooted many times, and taken the battery and sim card out multiple times as well. No change in the outcome and i have even taken the scree protector off to see if it was my had. the bottom of the phone works, ie the back button and left side button, but the screen itself does not work. i have just recently gotten a new screen and front housing so I don't know if that is the problem. Any suggestions?