Laptop give loud noise sound when switch on

[challamcsc]

Hello,
when i start my laptop a loud very noise is starting... and the cpu fan is running for 4 or 5 second then stop...

 

[nikorr]

Some laptops do that, its part of the start up check, system just making sure its working fine.

 

[CaedenV]

It is just the fans spinning up before BIOS takes control. Perfectly normal for budget (and even some higher end) laptops and PCs to do this. If they spin up, and then stay loud, then be worried that something is wrong.