Question Acer Nitro 5 making crack noise

[Gamdjdj]

Hello, I have a question, so I have an Acer Nitro 5 which has a HDD. I play games on it for 1 hour usually with fans running around 5k-6k RPM and soon as I turn the game off, my laptop makes a CRACK noise. I have no idea from what this crack noise is coming, it sounds like cracking in motherboard. If laptop's motherboard gets cracked, will it make sudden damage? As in computer will turn off suddenly or it'll stay on for a little? What will be impacts of a motherboard damage? And if this cracking noise is coming from something else then what it can be? Are fans or the ball berring inside making this crack noise? Is it safe or there's some problem in my laptop?