Stop, in the name of something

One of your computers is randomly giving a blue Windows STOP error multiple times a day. The problem always occurs when the processor is under heavy use, such as video rendering or graphics editing. The computer runs without any errors the rest of the time. Which of these would be the best start for troubleshooting this problem?

A) Perform a hard drive diagnostic

B) Check the system for overheating

C) Examine the USB port power usage

D) Update the video driver

E) Play soft music and burn incense. For you, not the computer.