BIOS problem w/ USB input??

So, all of a sudden when I plug a USB device into the front of my compter (external soundcard, camera) the entire screen turns blue and my computer starts going *ding ding ding ding ding* like I won a slot machine. Then the attached message talking about a memory dump comes up and my computer freezes forcing me to restart. I have a 40GB hard drive which is about 1/2 full after I defragged last week. I've never had this problem until now. Any suggestions? Thank you!