root@shinobi [system/cpu/cpu0]# dmesg |grep -i power
ACPI: Power Button (FF) [PWRF]
ACPI: Power Button (CM) [PWRB]
ACPI: CPU0 (power states: C1[C1] C3[C3])
powernow-k8: Found 1 AMD Athlon 64 / Opteron processors (version 1.50.4)
powernow-k8:    0 : fid 0xc (2000 MHz), vid 0x4 (1450 mV)
powernow-k8:    1 : fid 0xa (1800 MHz), vid 0x6 (1400 mV)
powernow-k8:    2 : fid 0x8 (1600 MHz), vid 0x8 (1350 mV)
powernow-k8:    3 : fid 0x0 (800 MHz), vid 0x16 (1000 mV)

root@shinobi [system/cpu/cpu0]# dmesg |grep -i freq 
Losing some ticks... checking if CPU frequency changed.