Well, either way, the card's broken, so just RMA it, say it was a **** job, never say the real reasons why it's broken, when you call em, tell them you plugged in your screen, and everything went crazy and then describe all the artifcating and everything.
Though I can assure you that plugging/unplugging a screen while computer is on, whether it's a VGA, DVI, HDMI,... cable/connector, nothing of that magnitude can happen, only thing I've seen happen is the screen flicker because I didn't plug it in firmly enough.
