Fuchsiii~~~@faizalr mine does show a power LED when plugged in to the charger. But when I press the on button the LED turns of and nothing happens. Thats why I suspected a broken mainbaord. But now that I put a working (as far as the seller wrote) one in it and the same thing happens... the only thing I can think of is that the DC power jack is somehow broken. Its weird...
Kevin Karhan 
@fuchsiii @faizalr I suspect the power managment system to have issues.
Basically what goes between the external 20VDC-in, VBAT and VDCpower internal (I assume 12V/5V/3,3V rails)...
Pretty shure there's something like a #ISL9239 / #ISL9240 or TI-made PMUX that goes from those two power rails - or at worst there's just one and the VBAT & Power Rail gets spliced out of one voltage downconverter...
At this point I'd consider looking up https://laptopblue.vn or other sites for #schematics and #BoardViews like #LouisRossmann does...