Dell inspiron 14 5000 2-in-1 suddenly off.

Hi

My guess is a loose component / damage to the Main Board.

Which suggests you have to open it up and investigate.

@ann_droid​ A hardware review has been carried out and no damage or loose parts were found. The performance of all hardware is still good.

As additional information, the issue appears more often after an update is made to the BIOS. In addition, there is a decrease in performance on battery life, whether this is also influenced by the BIOS update or not.

@Azmiag12​ 

Has the CMOS coin cell battery been changed since 2021?

@ann_droid​ it has never been replaced. Nevertheless, the only issue if CMOS cell battery dies are all BIOS settings will be reset, the time and date will be inaccurate, and will also be unable to save BIOS settings.

In my case, my laptop still can normally wake up by 48 hours after that suddenly shutting down. However, this causes a lot of work to be neglected due to this condition.

You either have one or more chips that are failing internally or marginal wire traces -- either way, the system needs a mainboard, if you feel the cost of replacing it is economic.