How to Clear the Sun Fire X4640 Server CMOS Settings

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Caution - Loss of customized information. Removing the battery erases customized settings stored in the battery-backed CMOS. Erasing custom settings might render your server inoperable within your environment.

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Before You Begin

• You need a jumper cap to short the pins of the jumper.

• Make a note of any customized settings in the BIOS Setup utility, so you can enter the values into the utility after clearing the CMOS.

1. Prepare the server for service using the steps described in the section, How to Prepare the Server for Service.
2. Install the jumper cap across the Clear CMOS jumper (P25) header pins. See Sun Fire X4640 Server Motherboard Jumpers and Switches.
3. Wait 10 seconds, then remove the jumper cap.

   Shorting the jumper removes battery power from the SouthBridge chipset where the CMOS settings are stored. This action clears the CMOS and restores the settings to the default values.

4. Prepare the server for operation using the steps described in the section, How to Prepare the Server for Operation.

Next Steps

• If necessary, access the BIOS Setup utility to customize the settings for your environment. See Configuring the System Using the BIOS Setup Utilities.

See Also

• Sun Fire X4640 Server Motherboard Jumpers and Switches

• Configuring the System Using the BIOS Setup Utilities

• How to Power On the Server