Solution
When a power supply blows up it is unfortunately not uncommon for it to damage the motherboard as well. Fortunately all of the other parts of the computer such as the hard drive, CPU, memory and graphics card normally survive. The chances are that it is just the power supply that is faulty I hope that you are lucky.
If you had a quality brand psu then most likely not because the better brands have more protection to not let damaging spikes go through the cables. I had a psu actually blow up in my computer with tons of smoke and sparks , if you would have seen it you would have said that everything just got fried but the only thing damaged was the psu. Chances are good that your hdd is ok.
 
When a power supply blows up it is unfortunately not uncommon for it to damage the motherboard as well. Fortunately all of the other parts of the computer such as the hard drive, CPU, memory and graphics card normally survive. The chances are that it is just the power supply that is faulty I hope that you are lucky.
 
Solution