7" Super? Sounds like you have one of the monitors being discussed in this thread:
New ebay LCD
Seems like it is not getting power but I have tested the power, checked the fuses but nothing powers up. The USB touch screen part is working, at least I hear it being recognized by WinXP, but all of a sudden while driving the screen goes black and I get nothing! Any one else have this issue, it is branded "Super" on the screen, looks like a typical 7" VGA touch screen you see everywhere.