LCD Screen

The LCD screen in my computer was cracked and had to be replaced. The original screen was a Toshiba 15.4 in WUXGA with a part number of LTD154LZ0S. The replacement screen that they said was comparable is a Samsung 15.4 in WXGA part number LTN154X3-L01. When I hook up the new LCD screen and fire up my laptop, the screen is entirely black. I can hear the computer running and can log on by entering my password even though the screen is blank as I know the steps. If I hook up the old screen, everything is fine except for the area that is cracked on the original screen. Any thoughts on how to troubleshoot/fix this problem would be greatly appreciated