Why Did i get a blue screen

[Vortex Hawk]

So i have an r9 270x. I can run all games on ultra but when i was playing watch dogs a solid blue screen appeared and froze. It had no error code or anything. I suspect it was my cpu overheating or something coz the fan was running really fast. Does anyone know for sure what caused this. ☺

 

[ss202sl]

Since the fans were going fast, It would seem to be a heat issue. What are your temperatures? At idle, and under load. Look at CPU and GPU.