Compaq Armada V300 CMOS Battery 468824-001 3V 75mAh

Compaq Armada V300 Series — 3V Lithium Replacement Battery (468824-001)

This is a 3V, 75mAh lithium CMOS backup battery for the Compaq Armada V300, M300, E700, and M700 series laptops. It fits the OEM part number 468824-001 and sits on the motherboard to power the RTC circuit and retain BIOS settings when the laptop is off or unplugged. Without a functional cell, the system loses date, time, and BIOS configuration every time mains power is removed.

• Armada series motherboard fit: The V300, M300, E700, and M700 platforms share the same CMOS socket layout and retention voltage threshold. All rely on a 3V lithium cell to back the SRAM that holds BIOS parameters and the RTC oscillator circuit between power cycles.
• Bench tested on actual hardware: We confirmed the cell holds above the 2.8V minimum retention voltage threshold required to maintain SRAM state. The RTC circuit stayed active and settings persisted across full power removal during testing.
• Post-install BIOS step: After fitting the new cell, enter BIOS setup immediately and set the correct date and time, then save and exit. The RTC resets to a default value after any power interruption — the new cell will hold whatever you set, but it cannot recover the previous values on its own.

BIOS clock resetting to a default date after every power cycle

The Armada series uses the CMOS cell exclusively to power the RTC circuit when AC and main battery power are absent. When the cell drops below approximately 2.8V, the RTC loses power during shutdown and resets to a hardcoded default date — typically January 1, 2000 — on the next boot. This is not a BIOS fault. The cell is simply no longer supplying enough voltage to hold the RTC oscillator between sessions. Replacing the 468824-001 cell and then setting the correct date in BIOS resolves the cycle permanently.

CMOS checksum error on boot after fitting a new cell

A checksum error after a cell swap usually means the BIOS detected that CMOS memory was cleared — which happens whenever the cell is fully depleted or physically removed. The BIOS recalculates the checksum against stored settings; if the SRAM contents are gone, the checksum fails and the system halts for user confirmation. This is expected behaviour, not a fault with the new cell. Enter BIOS setup, verify or restore your settings, save, and exit — the error will not reappear as long as the new cell stays above 2.8V.