What causes an IC to glow RED hot?
I guess it could be a lot of things, anything that causes a short inside any IC could cause this, maybe a high ESD spike hit the IC and it fused some of the transistors.  But if I had to venture a guess in regards to the video: 

That IC is the motor driver for the spindle motor and that location on the IC is where the drive transistor is located.  The IC is controlling 12V to the motor and a computer power supply can provide a lot of current at 12V, supply in my computer has 4 25A +12V rails.

If something had happened to the spindle motor that locked it in place, the drive current would be massive (think the start up current for a DC motor but never reducing once its spinning).  The current was enough to push the drive transistor past its thermal breakdown point and it got hot enough to melt the IC package, resulting in the hole and the glowing.