Dell Vostro 3500 CMOS Replacement Battery 3V GC02000LB00

Dell Vostro 3500 Series — 3V Lithium CMOS Backup Battery (GC02000LB00)

This is a 3V, 200mAh lithium coin cell for the Dell Vostro 3500, 1510, 1310, and 1015 motherboards. It powers the RTC circuit and CMOS SRAM, keeping system time, BIOS settings, and boot configuration intact when the laptop is off or unplugged. Replace it when the system clock resets on every power cycle or BIOS settings fail to save.

• Vostro 3500, 1510, 1310, 1015 motherboard fit: These models share the same RTC circuit layout and coin cell socket spec — 3V retention voltage, same physical footprint at 26.25 × 20.12 × 4.60mm, and the same contact spring orientation on the motherboard header.
• Bench tested on actual hardware: We confirmed open-circuit voltage at 3.0V and verified that SRAM retention held stable across repeated mains-disconnect cycles. The CMOS checksum passed on each cold boot after installation.
• 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 circuit resets to a default value on any power interruption — the cell alone does not restore the clock, only retains it once set.

BIOS clock resetting to 2000 after every power cycle

The Vostro RTC circuit requires a minimum retention voltage of 2.8V from the CMOS cell to hold the clock register during mains-off periods. Once the coin cell drops below that threshold, the RTC loses power and defaults to its factory timestamp — typically 1 January 2000. A degraded cell can still show 2.9V on a multimeter at rest but collapse under the microamp draw of the RTC circuit. Replacing the cell and setting the clock in BIOS resolves this immediately.

CMOS checksum error on boot after fitting a new coin cell

A checksum error after a new cell install usually means the BIOS detected a mismatch between stored settings and what the CMOS SRAM now contains — which is nothing, because the swap interrupted power to the circuit. This is expected behaviour, not a faulty cell. Enter BIOS setup, confirm or restore your settings, set the correct date and time, then save and exit. The checksum regenerates on save and the error clears on next boot.