Flashing BIOS may cause CMOS checksum error - IBM System x3610 (Type 7942)

Resolving The Problem

Source

RETAIN tip: H193676

Issue

A CMOS checksum error occurs after upgrading BIOS from version 1.00, Build ID BHJT06A, to any later version. The following error message during POST may appear:

A CMOS checksum error and system date/time will be restored to default if downgrading any BIOS versions back to version 1.00, Build ID BHJT06A. The following error messages during POST may appear:

Affected configurations

The system may be any of the following IBM servers:

• System x3610, type 7942, any model

This tip is not option specific.

This tip is not Operating System specific.

Additional information

The system feature enhancement is required to implement in BIOS version 1.01, Build ID BHJT15A. The CMOS allocation is modified from BIOS version 1.00, Build ID BHJT06A to 1.01, Build ID BHJT15A in order to meet the feature enhance requirement. The CMOS checksum error does not affects system functionality.

However, the password and customize CMOS setting will be lost and restored to default after flashing the system BIOS. A proper CMOS backup action is required before upgrading the BIOS from version 1.00, Build ID BHJT06A to any later BIOS version. The system with BIOS version 1.01, Build ID BHJT15A and later, is not affected.

System BIOS downgrading is not recommended, especially with BIOS version 1.00, Build ID BHJT06A. System CMOS checksum error and date/time restored to default will occur. It is highly recommended to backup the BIOS CMOS setting before downgrading the BIOS, and adjust the system date/time after BIOS downgrading.

However, after BIOS 1.01, Build ID BHJT15A, as long as you flash up, you will not have a problem. If flashing down to 1.00, Build ID BHJT06A from any level, a System CMOS checksum error and date/time restored to defaults will occur.