MSI Cubi B3500U (MS-B096) – BIOS loses settings after power loss (Ubuntu, new battery, BIOS update/downgrade didn’t help)

[ebu330]

Hi everyone,


I’m having an issue with my MSI Cubi with the following details:

• Model: MSI Cubi B3500U
• Barebone / Mainboard: MS-B096
• Serial Number (S/N): MSB096F4S0108573
• CPU: Intel Core i3
• Operating System: Ubuntu Linux

Issue:
The BIOS loses all settings once the system is completely disconnected from power.


Behavior:

• A normal reboot works fine and settings are kept
• As soon as the system is fully unplugged from power, on the next boot:
  • Date & time are reset
  • BIOS settings are lost (e.g. boot mode)

What I already tried:

• Updated BIOS to the latest version → no change
• Downgraded BIOS to an older version → no change
• Replaced the CMOS/BIOS battery (CR2032)
• BIOS settings are saved properly using F10 → Save & Exit
• The issue happens only after complete power loss
• Ubuntu runs fine → issue is OS-independent

The system itself is stable, but the BIOS behaves as if a CMOS reset occurs every time external power is removed, even with a new battery.


Has anyone experienced this exact issue with an MSI Cubi / MS-B096?
Is there a known fix or workaround (super capacitor, board revision, BIOS bug)?
Or does this point to a mainboard hardware defect?


Thanks in advance!

 

[plutomate]

When you say you replace CMOS battery, does the problem occur right away or after a period of time? Just wanna see if it could be hardware problem that accidentally drained the battery.
Can you recall if you done anything before this happens?

 

[FlyingMog]

This is a CMOS CR2032 lithium battery with a wire lead and connector. Please check that you are using the correct one and that the positive and negative terminals are properly installed on the motherboard.