Question

[Exdominator]

(noticed this after using pc for hours but usually outside of intensive workload, altho it may also happen in intensive workload but since i mostly play games and i have headphones i may not hear it/pay attention) 
Sometimes after using my pc for some hours the fans spin like crazy (im guessing max speed) for like 0.5-1 seconds and then proceed to normal speed.
So what could be causing this and is it dangerous?
Specs are G4400 with gtx1050 and PSU 400W ATX FORTRON. Everything has its stock's fans (as far as i know they are enough for my system)

[wildgg]

the fan is probably set in bios to go 100% when hitting certain cpu temps, easiest way to test this is downloading a cpu stress test like aida64, run the stres test with cpu and fpu checked.

keep an eye on temps and see if the fan still ramps up.