How to find processor speed on Linux OS

The File called cpuinfo_max_freq contains the maximum frequency in KHz

[root@lenovo ~]# cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq
3000000

(OR)

[root@lenovo ~]# cat /proc/cpuinfo
processor    : 0
vendor_id    : GenuineIntel
cpu family    : 6
model        : 23
model name    : Intel(R) Core(TM)2 Duo CPU     E8400  @ 3.00GHz
stepping    : 6
cpu MHz        : 2000.000
cache size    : 6144 KB
physical id    : 0
siblings    : 2
core id        : 0
cpu cores    : 2
apicid        : 0
initial apicid    : 0
fpu        : yes
fpu_exception    : yes
cpuid level    : 10
wp        : yes
flags        : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 lahf_lm dts tpr_shadow vnmi flexpriority
bogomips    : 5984.89
clflush size    : 64
cache_alignment    : 64
address sizes    : 36 bits physical, 48 bits virtual
power management:

processor    : 1
vendor_id    : GenuineIntel
cpu family    : 6
model        : 23
model name    : Intel(R) Core(TM)2 Duo CPU     E8400  @ 3.00GHz
stepping    : 6
cpu MHz        : 3000.000
cache size    : 6144 KB
physical id    : 0
siblings    : 2
core id        : 1
cpu cores    : 2
apicid        : 1
initial apicid    : 1
fpu        : yes
fpu_exception    : yes
cpuid level    : 10
wp        : yes
flags        : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good aperfmperf pni dtes64 monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr pdcm sse4_1 lahf_lm dts tpr_shadow vnmi flexpriority
bogomips    : 5984.89
clflush size    : 64
cache_alignment    : 64
address sizes    : 36 bits physical, 48 bits virtual
power management:

(OR)

[root@lenovo ~]# dmesg | grep CPU
SMP: Allowing 2 CPUs, 0 hotplug CPUs
NR_CPUS:4096 nr_cpumask_bits:2 nr_cpu_ids:2 nr_node_ids:1
PERCPU: Embedded 31 pages/cpu @ffff880002200000 s94872 r8192 d23912 u1048576
CPU: Physical Processor ID: 0
CPU: Processor Core ID: 0
mce: CPU supports 6 MCE banks
CPU0: Thermal monitoring handled by SMI
CPU0: Intel(R) Core(TM)2 Duo CPU     E8400  @ 3.00GHz stepping 06
CPU1: Thermal monitoring handled by SMI
Brought up 2 CPUs
microcode: CPU0 sig=0x10676, pf=0x1, revision=0x60c
microcode: CPU1 sig=0x10676, pf=0x1, revision=0x60c
microcode: CPU0 updated to revision 0x60f, date = 2010-09-29
microcode: CPU1 updated to revision 0x60f, date = 2010-09-29