Waterdamagd series s

hello

i bought a series s for €35 the told me it got water damage, as i repaired multiple switches with water damage, i wasnt scared

so i opened it up to find the blue corrosion on the board, i cleaned it wit alchol,but still no luck, the fan spins, the power button lights up a sec, and sometimes i am hearing a crisping eletrical sound.

any ideas?