no one any idea?

Hi im new here and i hope you guys can help me maybe.

I buyed an old Asus G750JX and the seller told me it was running perfect after shutdown it never bootet again.

So i buyed this G750JX and open it. after cleaning and checking all inside i startet it.
It was booting perfectly. i played a clean win 8.1 on it.

After installing all and update all to the last drivers it was running very good.
Thinks that dont worked
Keyboard back lights and cant start with fn+f4 all other fn+f working
3 of the 4 USB 3 Ports are not working.
the...