I recently got an older 15" MB Pro (2 GHz, A1150 model) for $50. The previous owner took it to an Apple Store and was told it would cost a fortune to replace the display. I bought a new LCD screen on-line (just the screen, not the entire display) and installed it yesterday and I still don't get an image. If I connect an external monitor I can see the everything as normal. Under Displays I get the message:
Display Connector - Status: No Display Connected

So now I am thinking either:
1) I got a bad screen
2) The inverter board is out
3) The display cable is bad for some reason
4) ??The mother board is defective??

Does anyone have any suggestions on where to go from here?

Thanks
PBJ