Is the motherboard. But the cost is too high to consider this. I'd use it as-is until you can move to your next PC.
Keep an eye on the next links.
https://h30434.www3.hp.com/t5/Notebook-Hardware-and-Upgrade-Questions/laptop-dv7-screen/td-p/6276228
https://h30434.www3.hp.com/t5/Notebook-Video-Display-and-Touch/Laptop-screen-flickering/m-p/6296789
https://www.ifixit.com/Answers/View/419537/Back+lighted+screen+but+black%2C+works+on+external+video notes there is no inverter in LED models.
https://forums.techguy.org/threads/hp-laptop-screen-flickering.1195548/ notes the incorrect model number. If you are going to cross post, correct as you post other places.
https://support.hp.com/us-en/product/hp-pavilion-dv7-3000-entertainment-notebook-pc-series/4011368/model/4030073/product-info
I see the 160 buck motherboard at http://www.laptopcpufan.net/hp-pavilion-dv7-3069wm-laptop-motherboard-lf.html
http://forum.notebookreview.com/threads/hp-black-17-3-pavilion-dv7-3069wm-598-00.437816/ gives me enough detail that I'm going to write "DO NOT REPAIR." Start shopping.
https://www.groupon.com/goods/laptops?display-size=79309123-ccae-4454-8c08-e05da49daa95 finds newer 17 inch models in the Walmart price range you paid for this one.
HP Pavillion DV7-3089wm
Laptop running Win 10
Laptop screen will light up but stays mostly black and then starts flickering like bad connection and then will go black again untill I wake it up and then I can see the screen pic when flickering.
What I have found so far and what I have done:
The external monitor works just fine''' Have no problem using on external monitor.
I replaced the screen and the video cable and checked all connections.
I have inspected all connections and cabels.
At this point I have reached the end of ideas. Would appreciate any suggestions.

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