My Acer Aspire 5750z laptop was not charging the battery, so I took it apart and re-soldered the connections on the power jack (which I could see had physically broken loose). When I put it all back together and powered it on, the screen did not turn on at all and I can not get a signal through hdmi either. It powers on fine and actually charges the battery now, but this doesn't matter if I can't see anything anyway. This laptop has the video card integrated into the motherboard, so I'm hoping I won't have to replace that. Anyway, any ideas for what it could be or is it most likely the motherboard? Also, if it is that, would it typically be cheaper to replace that or get a tech to repair it?