Crash to desktop randomly seemingly when I cast a spell
 

This has happened to me 3 times in the last 30 minutes and caused some not so fun deaths and exp loss. It's happened all 3 times during fighting, and seems to happen after I cast a spell (although I can't confirm 100% that it has anything to do with it. I've had zero technical problems with this game up to this point.

I get no error message. It just goes from in-game to the desktop. I can reboot right back up and find myself dead at the bind point (obviously due to death). Any ideas? I just did a Windows 7 update earlier today that included an upgrade to IE 9, but I don't know if that had anything to do with it as I got in several hours of gameplay after the update error free.

edited for some additional information