The issue deals with the game's interactive menu screens that pop up between missions, where Jim Raynor can explore his flagship and chat with crew. While the rest of the game has limits on what can be rendered, the menu screens have no framerate cap whatsoever, and some computers will interpret this to mean "go hog wild." Rendering framerates of over 200 frames per second for extended period of times means that computers with insufficient ventilation melt themselves into oblivion. And that means you can't play SC2, and we don't want that.
The fix: A temporary workaround is to go to your Documents\StarCraft\variables.txt file and add these lines:
My screens weren't being affected or anything but I did this anyway because the computer was getting kind of hot. It didn't affect my gameplay at all, so that's good.