It's a mosfet transistor, i would guess by its location it is a part of the voltage regulation of the RAM. Are you sure that's the problem your motherboard doesn't work? If you are still within warranty I would ask for a replacement, otherwise you can buy a similar transistor and solder it. You always have the option of buying a new motherboard but that is obviously more expensive.
Well, when I turned computer on - I heard *Zap* and some plastic smell and immediately took powers off and tried to search damages, and that was the only one I found.
My system (now only cpu, psu and mobo) only starts only for 2-3s (fans only, no beeps or nothing)
@Someone Where
Well I can see some metal inside.
But well, maybe I should go to vendor and ask if there is anything to do or just buy a new one.