Linux hardware information tools misreport DDR2 memory speeds - IBM System x3550 / x3650

Resolving The Problem

Source

RETAIN tip: H195721

Symptom

When running the dmidecode command in Linux, the reported speed of the Double-Data-Rate 2 (DDR2) memory will show as 266 MHz when the actual speed is 667 MHz. This issue can be seen when running dmidecode, lshw, and other Linux hardware information utilities that pull hardware information from the DMI table of the Basic Input/Output System (BIOS). There are no errors; this is only a reporting issue where the information being pulled from the DMI table of the BIOS for the memory speed is incorrect.

The following is sample output from Linux when running the dmidecode command:

In the example above, the memory speed is listed as 266 MHz, but the correct speed is 667 MHz. There is no issue with the memory, and it is running at 667 MHz.

Affected configurations

The system may be any of the following IBM servers:

• System x3550, type 7978, any model
• System x3650, type 7979, any model

The system is configured with at least one of the following:

• Red Hat Enterprise Linux 3, any update
• Red Hat Enterprise Linux 4, any update
• Red Hat Enterprise Linux 5, any update
• Red Hat Linux 5.0, any update
• SUSE Linux Enterprise Server 10, any Service Pack
• SUSE Linux Enterprise Server 10 for AMD64/EM64T, any Service Pack
• SUSE Linux Enterprise Server 11, any Service Pack

This tip is not option specific.

• The dmidecode utility is affected.

The following system BIOS level(s) are affected:

• Version 1.14 - Build ID: GFE144A and previous.

Note: This does not imply that the network operating system will work under all combinations of hardware and software. Please see the compatibility page for more information: http://www.ibm.com/servers/eserver/serverproven/compat/us/

Solution

This behavior will be corrected in a future release of Basic Input/Output System (BIOS) that will correct the BIOS DMI table. The target date for this release is scheduled for third quarter 2009.

The file will be available from the IBM System x Support web site at the following URL:

Workaround

There is no workaround as this is a misreporting issue. The user should disregard the memory speed that is being reported.

Additional information

The dmidecode utility reports information about the system's hardware, as contained in the system BIOS. This is occurring because DMI table of the system BIOS is incorrectly reporting the memory speeds as 266mhz, instead of 667mhz. There is no workaround at this time. The next BIOS update will provide the fix to the DMI table of the system BIOS. This update will correctly report the correct memory speed of the installed memory.