Throw the computer out and buy a new one. If you think this advice is unacceptable, it is no less unacceptable than the information you provided and considering such, the best solution I can give you based on the info.
Plug-N-Play shouldn't shutdown a pc, unless power circuit is iffy causing psu to switch off, check that the cable plugged in to the motherboard are the right way, have know people to plug in usb cables that are seperate strands on to the wrong pins.