Dell latitude d620 killing lcd?

I'm here to bother you guys about a laptop I've got it's a dell latitude d620. I've been through 2 lcds and 3 ribbons nothing seems to help. the computer boots just fine the problem is with the screen the computer starts but there is a... I dont wanna call it lines but i think its what they are, you can only tell the difference in small areas like the outline of the mouse, or the letters in the menu, overall it looks like it has a bad resolution. but i know that's not it. I've run w7 and multiple linux distros to make sure it isn't it. The bios as updated and I'm sure is not a driver issue it also happens when I'm in the boos menu. I have a dell d630 so every time I've gotten a bad lcd I cross check it with the 630 and so far i've gotten 3 bad lcds from people on ebay. Not to my surprised I've gotten my money back and now the guy even offered to test one and ship me one that works. I received it, but I'm still experiencing the same problem. I've tried 3 different lcd ribbons and nothing what should i do next? I've tried the image in an external monitor and it's just fine. the only problem is with an lcd. I almost feel like the laptop is killing lcds. Thank you for your time

Yeah it's fine in an external monitor I though do at first I know the 630s are famous for their nvidia chips going bad.