It's not necessarily a dead loss you may have lost just one component there and its nocked out the whole system, leave it to dry for a good long while. If it's a series of motherboard shorts and not just say the CPU or the power supply. You could be in for some extensive reconstructive surgery or a whole new build though, my advice wait and see, you'll need to get it looked at, but be careful, some computer stores are little better than shody mechanics, and they may tell you the whole things shot, get a second opinion in that case.
I work with someone who gets frequent water damaged electronics, usually it's just a chip problem and replacing that sorts it out, ocassionaly if your lucky and the shorts are not causing actual damage it may work after drying out, but in a PC this is probably unlikely.
