R410's shipped out with BIOS showing 4 cores instead of 8

Matt Domsch Matt_Domsch at dell.com
Wed Feb 3 11:22:59 CST 2010

On Sun, Jan 31, 2010 at 10:05:40AM -0600, Rahul Nabar wrote:
> Has anyone seen this problem before? I have dual socket Nehalems with
> twin quad core chips. When I booted the OS it showed only 4 cores. I
> went to the BIOS and found under Processor Settings the entry
> Cores-per-processor set to "Dual"

This is not intentional.

There are several ways to resolve this.

A) Go into BIOS SETUP and change Processor Settings, Cores per
processor from "Dual" to "All" and reboot.

B) Use Dell Deployment Toolkit.  The SYSCFG command can reset this
value.  From the documentation:

  SYSCFG --cpucore 1, 2, 4, 6, 8, 10, 12, all
  This option controls the number of enabled cores in each processor.
  The default value is set to the maximum number of cores per processor.
  A:>syscfg --cpucore=1

Documentation at

Deployment Toolkit can be downloaded from support.dell.com.  DTK runs
under several environments, including WinPE and Linux.

C) Use Dell OpenManage Server Administrator (OMSA).  The omconfig
command can reset this value.  From the documentation:

   omconfig mainsystem biossetup attribute=cpucore setting=1 | 2 | 4 | 6 | 8 | 10 | 12 |all
   1: Enables one core per processor.
   2: Enables two cores per processor.
   4: Enables four cores per processor.
   6: Enables six cores per processor.
   8: Enables eight cores per processor.
  10: Enables ten cores per processor.
  12: Enables twelve cores per processor.
 all: Enables the maximum cores per processor.

Documentation at

 $ sudo omconfig mainsystem biossetup attribute=cpucore setting=all

OMSA can be downloaded from support.dell.com or from the hardware
repository on http://linux.dell.com/repo/hardware/ .  OMSA runs under
several environments, including fully Dell Supported operating

D) Under Linux, use smbios-token-ctl to change the value.
smbios-token-ctl is available in the smbios-utils-python package from
your from your favorite Linux distribution, or from EPEL if using
RHEL{4,5}.  Install using 'sudo yum install smbios-utils-python' or
equivalent for your distribution.
   $ sudo yum install smbios-utils-python
   $ sudo /usr/sbin/smbios-token-ctl --activate -i 0x026e

When using any of the above methods, after a reboot, you'll see all
your cores.

> Why is such an entry present in the first place?

For specific application performance reasons, and on occasion for
specific software licensing reasons, it may be desirable to disable
cores at the BIOS level rather than the OS level.


Matt Domsch
Technology Strategist, Dell Office of the CTO
linux.dell.com & www.dell.com/linux

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