Hi Barrabus,
When you say "power plug", do you mean the power supply or the power cord? Where exactly was this fuse located?
If the case you bought was extremely inexpensive, then the power supply may have been made with sub standard parts to meet cost levels. I've seen really cheap ones go out fairly quickly on a regular basis, but have yet to see a good quality one die prematurely. Replace the power supply (if this is the part the fuse was located in) with a good quality one and try your board again. The fuse should have protected the board from any surge.
If the fuse was located on the motherboard, replace it and try again. If the fuse blows again, then something is definitely wrong and you'll have to have the power supply checked out as it's probably not regulating the power correctly.
Hope you can isolate the problem.
Cricket