I think that might in fact be a inverter. I looked up dv3015 on hppartsurfer and it has a part 468798-001 for a inverter board. I'm just guessing at model since I don't know your exact model outside it being a dv3000. I hardly work on HP, but new gateway and acer units that use led displays have that built into the display. Event he plug on that circuit board you took a picture of looks typical of the same plug thats on the led display.
Normally I would say the inverter has nothing to do with your video feed it only supplies back light, but in your case I'm not so sure. As the led displays that have that circuit board built in also only have one connector that apparently gives video feed and power to the led back light. How many cables plug into the lcd you have? Is there one for that circuit board and one coming from the system board? Or is it from the system board to that board then to the lcd? If the ladder it could very well be that board that is bad.
I have seen that issue before many times in normal lcds and its usually either the lcd cable or the lcd itself, and sometimes its the damn lcd connector on the system board with a cracked solider joint (rare).
might still be in warranty man. http://h20000.www2.hp.com/bizsupport...odTypeId=12454
check it out and facilitate that sucker. Unless you got an extended warranty then send it to them instead (free shipping). Good luck