Flashing Led on Cpu cooler

[DRJ1014]

I got a new CPU cooler. (coolermaster jet 9) it has a white led flashing light on it. today it seemed like it was going faster than usual. i could find the box to see if it went faster when it got hotter but i couldnt find it so i asked my friend and he said it has a temp gauge in there but for some reason i dont believe him. is it just me or does it flash faster when it gets hotter