MSI GF62-8RE black screen

[Sparky]

I am trying to repair this laptop with no luck. Symptoms were no display, KB lights up, HDMI has no output. When it 1st came in I noticed the GPU fan not spinning. The CPU fan was spinning. So I ordered a pair of fans to replace both since they both were 3-4 years old. Take it apart, clean out the dryer like lint blocking the fins and new thermal paste.
I kept the back cover off and turned it on. Keyboard rgb lights turn on, GPU fan not spinning and no display. All same as before. Swapped memory slots. I dont have another ddr4 sodimm 2400 or 2666 module to try.
Any suggestions?

 

[Sparky]

I meant suggestions on how to fix it. Not a replacement video card which wont fit in this laptop.

 

[pimp_squeak]

Reseat any cables that may have been bumped? No doubt my experience is less than yours, but I've had trouble with ribbon cables that were bumped only slightly out of alignment that caused problems till I went back and tweaked how they sat. Particularly this one circled in red. The position looks like it would be possible to bump it while re-installing the heatsink and it looks to have enough pins for a video signal.

Edit: Ignore me, just clued in that's the battery connection.