Ok, I just did many different combinations and, for the first time in about a week, the mouse doesn't shut my PC off when I plug it into that port. I plugged my Blue Snowball Mic into the troubled port, then my keyboard, both of which worked and did not shut the PC down. Then I tried my mouse, and it is fully functional. I have a feeling that monotron was right about something being stuck in it. Sorry for wasting your time, if it happens again (and I can't fix it), I will be back.