So why does this happen?
It’s simply, really. Your computer is getting too hot and it needs to cool down a bit. There are temperature sensors on your motherboard that tell the fan to go into high-speed to air-out the inside of your case to do this. Some computers have been known to spin up fast right from the boot sequence, too. It’s all dependent on the brand of computer, and how hot it tends to get. If you fan resumes normal speed, then you shouldn’t worry. If it keeps going for extended amounts of time, you may want to relocate your computer case, or, if that doesn’t help, you should consult a professional as your computer may be overheating.
~Andrew
