i have a very similar problem, i have a DV7 3020sa and the screen just didnt work one day neither does the touch pad media and volume control things and the wifi light is off, but the wifi still works. i've just HDMI'd it into my tv so basically i use th e tv as a laptop and bought a logitech wireless keyboard with touchpad from staples for £25 and all is good i can watch tv from itiplayer, skyplayer, itvplayer 4od etc. can use the computer from anywhere in the living room, watch tv) on it and the like. i don't know why i didnt do it before as the battery is dead and so i have to keep the computer constantly plugged in.
if your comp works, that might be a shout