Hi, we bought some machines with 2 x quad core Xeon E5405 processors and installed centos 5.3 on them. My problem is that I can't get the cpuspeed service to work. No driver seems to claim responsibility for the throttling and the fallback "modprobe acpi_cpufreq" in the cpuspeed init script just yields a "No such device" message. According to the acpi information the CPUs should support this just fine: cat /proc/acpi/processor/CPU0/info: processor id: 0 acpi id: 0 bus mastering control: yes power management: no throttling control: yes limit interface: yes cat /proc/acpi/processor/CPU0/throttling: state count: 8 active state: T0 states: *T0: 00% T1: 12% T2: 25% T3: 37% T4: 50% T5: 62% T6: 75% T7: 87% At least half of the cores aren't really used at the moment under non-peak load so we are wasting quite a bit of power with this. Any idea on how to get this working? Regards, Dennis