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HP ProLiant Servers

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Linux for ProLiant

Processor Notes

Customer action may be necessary depending on the Linux distribution. None of these issues are ProLiant server specific. Refer to the specific Operating System information below:
RHEL 4 Update 2 and greater (AMD64)
AMD PowerNow! is enabled by default beginning with Red Hat Enterprise Linux 4 Update 2 (AMD64).
No actions are required to enable or configure this feature.


RHEL 4 (AMD64) / RH EL 4 Update 1 (AMD64)
AMD PowerNow! is not supported on Red Hat Enterprise Linux 4 at this time.

AMD PowerNow! must be disabled on all systems. The following steps must be followed to disable AMD PowerNow!:

  • chkconfig --level 12345 cpuspeed off
  • Reboot the server


RHEL 4 Update 2 and greater (x86)
The following steps must be followed to enable and use PowerNow! with Red Hat Enterprise Linux 4 Update 2 and greater (x86):
  • Edit the /etc/cpuspeed.conf file and replace the line:
       #DRIVER="powernow-k7"
    with
       DRIVER="powernow-k8"
  • Add the boot parameter "clock=pmtmr" to the file /boot/grub/menu.lst
  • Reboot the system

RHEL 4 (x86) / RH EL 4 Update 1 (x86)
AMD PowerNow! is not supported on Red Hat Enterprise Linux 4 at this time.

AMD PowerNow! is not enabled by default on Red Hat Enterprise Linux 4 (x86) so no action is necessary.


SLES 9 SP2 or newer (AMD64)
AMD PowerNow! is enabled by default on all systems. No action is necessary to enable AMD PowerNow! functionality


SLES 9 SP1 (AMD64)
AMD PowerNow! must be disabled on all systems. To disable AMD PowerNow!, perform the following steps:
  • In the /etc/sysconfig/powersave/common file, replace this line    POWERSAVE_CPUFREQD_MODULE=""
    with
       POWERSAVE_CPUFREQD_MODULE="off"
  • Reboot the system

SLES 9 SP2 (x86)
The following steps must be used to enable and use PowerNow!:
  • Add the boot parameter "clock=pmtmr" to the file /boot/grub/menu.lst
  • Reboot the system

SLES 9 SP1 (x86)
ProLiant servers with dual-core processors:
AMD PowerNow! is not supported for dual-core processors under this operating system. To disable AMD PowerNow!, perform the following steps:

  • In the /etc/sysconfig/powersave/common file, replace this line    POWERSAVE_CPUFREQD_MODULE=""
    with
       POWERSAVE_CPUFREQD_MODULE="off"
  • Reboot the system

ProLiant servers with single-core processors:
The following steps must be used to enable and use PowerNow!:

  • Add the boot parameter "clock=pmtmr" to the file /boot/grub/menu.lst
  • Reboot the system