Hello I have a envy dv7-7238nr the backlighting works no picture. I tried uninstalling the display generic driver and video ati driver. I did get it to work after restart until I restarted again. then it disappeared. I have to use the display port hooked to a monitor to work on and that always works. I have unhooked the monitor while computer is on and the lcd led backlighting will dim out and come back on and make the noise for switching displays but that's it. I can dim the led backlight and brighten it also. THis laptop doesn't have a inverter I don't think like the pavilion. I can let it go to sleep with monitor hooked up and sometime when it wakes up they both will work until I restart the laptop.
I already said that it works good with an external monitor thats how was able to test. when the display does work I can open and close the lid all i want and the display will keep working until I restart it. I really don't think its the cable because i can loose it by just restarting it with out touching the lid. when I recovered it to see if it was a corrupt config file as long as it was in low resolution it worked and at first start up after recovery it worked until restart. i can only turn resolution down to 1280 x 768 . I tried that to see if lower resolution to see if it would work more consistently.