Last week my boss had a problem with the docking port in his laptop. When I connected it to another docking station, we got the same results and quickly concluded that the problem was the laptop itself and not the docking station. So we called Dell and got a technician on the line. Now, unlike most times, I got a good tech right off, and he quickly realized I was a technical person and in under 3 minutes had concluded the same thing I had—a bad motherboard. He set us up with a replacement and a technician to come out and replace it. This all happened on Friday.
Today when he got in, his docking station wasn't working. Fearing that the station he has at home was somehow frying the port on the laptop's motherboard, I ran down to his office with the docking station I have to test it out. I saw all the cables unplugged, and thought he did that in anticipation of me bringing the other station down. Fortunately, that was not the case. We'd never reconnected the power to his docking station after testing it last week.
Today's tech support troubleshooting lesson: Even if it sounds stupid, ask if it's plugged in first.