Freebook CW1557 / N5100 / Bios does not save settings

Laptops Freebook i3/i5/N100/150
1

Serial number ZFreeBCY2H220200404 / Purchased Aliexpress in 2023
Board: S105JW rev 1.2

Bios: ZW-BI-135-S105JWR120-JBC / EC ver 01.09

Problem: BIOS settings are not saved.

The laptop has thermal issues and now it is running without battery. So RTC should be lost when power is unplugged, but BIOS settings (such as disable Fast boot) should be persistant.

I need help to figure out how to unlock this situation. Being able to modify the CPU voltages (undervolting) will help to mitigate the temperature problem. Any advice on how to get the BIOS settings to save?

2

The problem could be a clogged or dirty fan.

It could be a dead BIOS battery.

3

Thank you Bruzan2025

This laptop does not have a fan; it only has a copper plate (covered with a black plastic that doesn’t help with cooling, nor it is not needed to avoid any shorts). Also it has too much thermal putty.

The BIOS chip is an FM25W128 / 2103J0G with non-volatile memory, so it doesn’t need a battery to save the CMOS.