I am in the process of trying to change out a broken LCD panel on a Dell XPS 15z laptop. I ordered a replacement on eBay, and have since installed it. The problem is, that when I turn the computer on, the back-light comes on, but there is no video. The Dell Part number is different on the new screen than it was on the old screen. My question is, do the part numbers have to explicitly match, or can they vary, and to what extent. I'm wondering that maybe this screen is different enough to the old one that, that is maybe why it won't work properly?