It's a model that has a design defect and long ago HP was replacing them with another model. What you write is in line with the design flaw and even if you reball or replace the motherboard that does not correct the defect.
Your choice to try things but my advice is to not invest a dime but sell it.
Hi
I have a HP DV9700 laying around, which I want to resurrect.
The screen was blinking red lights, I had the LCD cable replaced. But now it will not boot when the LCD cable is connected. When I disconnect that cable from the motherboard and I attach a regular VGA monitor. It boots up fine.
I had the inverter replaced aswell. The screen lights up again, but it will not boot. The screen stays completly black.
I heard about this reballing the GPU but i've been told that if my GPU is broken I wouldn't have gotten any video whatsoever out of the laptop, not even with an external monitor attached.
Can anyone offer me any assistance with troubleshooting this further?
Thanks in advance!

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