BIOS CMOS Battery Death Resets InTime Configuration¶
Networking / InTime Resolved All rigs (InTime-based, Windows PC)
Summary¶
The CMOS battery (CR2032) on the Flair PC motherboard maintains BIOS settings when the PC is powered off. When this battery dies, the BIOS resets to factory defaults on the next power cycle. If the factory default BIOS mode (UEFI vs. Legacy/CSM) does not match the mode used when Windows was originally installed, the PC will fail to boot — and InTime, which is part of that Windows installation, will be inaccessible.
This is a silent failure mode: the battery may be low for months before it dies, and there are no warnings. On old Flair PCs (5+ years), CMOS battery replacement is a routine preventative measure.
Symptoms¶
- Flair PC fails to boot after power-off; appears to boot into BIOS only
- BIOS clock is reset to a default date (1970 or a manufacturing date)
- Windows attempts to start but fails or loops with a recovery message
- Issue appeared after an overnight power-off or after transport
Root Cause¶
A dead CMOS battery causes the BIOS to lose all saved settings and reset to factory defaults. If factory defaults use UEFI mode but Windows was installed in Legacy/CSM mode (or vice versa), the bootloader cannot find the OS. InTime, as part of the Windows installation, is therefore also unavailable.
Resolution¶
Recovery¶
- Power on and enter BIOS setup (usually Del or F2 at boot).
- If BIOS shows no drive partitions, or shows drive as unreadable:
- Check CSM (Compatibility Support Module) setting in BIOS Advanced settings.
- If Windows was installed in Legacy mode: enable CSM.
- If Windows was installed in UEFI mode: disable CSM.
- Save and reboot.
- If three partitions are visible on the drive in BIOS, the drive is intact — just boot mode was wrong.
- If drive now boots: replace the CR2032 battery immediately.
Do not boot if you're unsure of the UEFI/Legacy mode
Niko (community): "The idea is to try not to boot if you don't know if your Windows was installed in legacy or UEFI. Check the disk before and select the right config of BIOS." Booting in the wrong mode on some configurations can corrupt the partition table.
Prevention¶
Replace the CMOS battery annually on all Flair PCs. CR2032 batteries cost very little. A boot repair program (if needed) costs significantly more, and losing a shoot day costs far more.
- Remove the PC side panel
- Locate the CR2032 coin cell on the motherboard
- Replace with a fresh CR2032 battery
- Re-enter BIOS and re-save all custom settings (including boot order, CSM setting, InTime BIOS configurations)
Save BIOS settings before replacing the battery
Photograph or document your current BIOS settings before replacing the battery so you can restore them exactly. InTime may require specific BIOS settings (e.g., PCIe power management disabled for the cifX card).
WhatsApp Excerpts¶
"If battery dies and BIOS resets to default and Windows is legacy installed, it will be too late. A preventive battery change (yearly) makes a lot of sense. CR2032 batteries are inexpensive." — Niko (2026-03-14)
"Before noticing the UEFI/legacy config I finished with 3 hard drives killed." — Niko (2026-03-14)
"If your UEFI screen shows three partitions, it means the drive is still fine. Go back to BIOS, turn on CSM, save and restart, then go back in BIOS and make sure it selects the drive as the boot." — Marc Srour (2026-03-14)
"The Flair Bridge is starting to look more and more appealing every day." — Dan Gottesman (2026-03-15, after this thread)
See Also¶
- NET intime dongle os drive — OS reinstall (e.g., after drive failure) requires new InTime licence
- NET windows updates intime — Other causes of InTime becoming non-functional