I think you have a dilema on your hands.
There is a chance you have shorted the motherboard if the fuse blew on the lead.
I can see what ron3003 is saying, and in some ways I agree.
Your post are very short (we don't get told what happens when you hit the power switch etc) so we are guessing a bit.
We like helping, but the more info you give us the better.
I have my doubts over that PSU being up to the job, but if you have a fried motherboard you are never going to know.