Hi, I'm having an issue with my display on my lenovo e420s. I just replaced the motherboard in the laptop. My issue is when I have the display plugged into the motherboard the computer wont turn on at all. when I disconnect the display from the motherboard it will turn on with the fan,harddrive, and processor running just like it normally should. Any ideas? I also have tried plugging into external VGA and nothing shows on the external screen. I haven't tried using HDMI yet but I will give a try when I get home.