Problems with motherboard and detection with PC Nexus 7 2012 16GB

Hello everybody,

I read a lot of from different sources and forums how to do "rise from dark", but these advices I know it and for my case not worked.

I bouth this tablet from since first day. I played games, watch films and everythings with tabled what it can normaly do - 5 hours per day sometimes less. Least 2 years (2015-2017) I use only little bit, because od version Andriond and I know battery hold for 3 hours max...

But half a year ago is dead completly. I think its againg problem with battery a take battery out and charge on inteligent charger without any problems. Put it back and not work.

So I start think what happend. I used also conneted with PC but device was not recognized.

And here is problem:

- Dont want turn on every possible combination with full charged battery.

- Dont want recognized with three different PCs with Win7 and Win10.

- No sound, no heat, no flashing I think also no charging. I used fortests Voice meter and Fluke IR camera not cheap devices.

I have really bad feeling about mainboard is damaged but how is this possible? I used tablet only at home and never dorp down to floor and nothing is break.

What do you think? or what I can try to be sure what is broken?

Big thanks for any advices

Noro