Problem Dell Vostro 14 3468 Bios control fan speed slow suddenly shutdown

Dear Dell,

My dell Vostro 14 3468 after update bios up v3.3.0 fan speed so so so slow then overheating shutdown.

I check my fan still clean only use one year 3 month. I think new bios Overclock my CPU.

https://www.dell.com/support/home/us/en/19/drivers/driversdetails?driverid=tprr5&oscode=w764

I use cooler pad ok cannot shutdown, why your do the fan speed control unstable bios to customer update.

I use ctrl+esc down to old bios version still same. Please give new bios fix fan speed very very slow.

Dell Vostro 14 3468 Motherboard model is Vegas/Turis SKL/KBL 15341-1 91N85

Spec is i3-7100U intel graphics, no AMD & Nvidia graphics. RAM 4GB DDR4.

After then start webcam problem in windows 10. This model really bad and motherboard unstable.

I update BIOS because login windows everytime windows 10 update show want Firmware Update.