can dead motherboards be fixed?

Hi
mobo fried, recently working. Now no longer powers at all. Power jack (is laptop mobo) was burned.

Getting no power from battery or ac, so think something else must have friend (possibly the separate mobo that this samsung p20 has).

Is there any way to repair/find where the fault is on such a motherboard?

Answers such as ‘take it to an electrician’ etc. not welcome – am talking about a solution at home, am an experienced computer techy (well, apart from this question)

Thanks
M

brighton electrics