Bdtyktl

There are a couple of ways:

1. 
   

   lscpu or more precise lscpu | grep "MHz".
   
   This will give you the general MHz for the CPU.

   
   
   

   $ lscpu | grep "MHz".
   
   CPU MHz:               1600.000
   
   

   
   


2. 
   

   cat /proc/cpuinfo or more precise cat /proc/cpuinfo | grep "MHz".
   
   This will give you the individual MHz for each CPU Core. So if you have an Core 2 Duo, AMD Bulldozer, Core i7, etc.. it will show the MHz for each core.

   
   
   

   $ cat /proc/cpuinfo | grep "MHz"
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 1600.000
   
   cpu MHz     : 3400.000
   
   

   
   


3. 
   

   lshw -c cpu or more precise version: lshw -c cpu | grep capacity
   
   Will give you the general MHz. Same as lscpu.

   
   
   

   $ lshw -c cpu | grep capacity
   
   WARNING: you should run this program as super-user.
   
          capacity: 1600MHz
   
   WARNING: output may be incomplete or inaccurate, you should run this program as super-user.
   
   

   
   


4. 
   

   sudo dmidecode -t processor or more precise: sudo dmidecode -t processor | grep "Speed" Will not only give you a MHz in use but also the Maximum you can push / overclock your CPU to.

   
   
   

   $ sudo dmidecode -t processor | grep Speed
   
   [sudo] password for cyrex: 
   
       Max Speed: 4000 MHz
   
       Current Speed: 2666 MHz
   
   

   
   

Out of all of this, lshw and dmidecode provide the best information out of your CPU.

You can also target the current MHz detected by the kernel by querying the log files:

cat /var/log/dmesg | grep "MHz processor" - For the current detected MHz speed

cat /var/log/kern.log | grep "MHz processor" - For the current and past detected MHz speeds. Will not work in some cases, that is why I posted the dmesg one first.

And that's all I can remember from the top of my head. I am fairly certain there are other ways, just don't remember right now. Of course, talking about terminal ways.

For the current CPU speed one can dynamically watch this change in real time using:

sudo watch -n 1  cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq

To see the maximum CPU speed, use:

cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_max_freq 

indicator-cpufreq-selector is a nice little indicator tool which shows your current cpu frequency. You can even select the desired cpu frequency.

However last update for this tool was on 2015-10-19.

I would just like to add i7z to this list. Contrary to the other options, this works better for CPUs in the i7, i5 and i3 series that have TurboBoost.

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies

I'd like to point out sudo is needed for Ian's answer above:

sudo cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq

However you can get the same results without sudo using:

cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cur_freq

My favourite is to use Conky where you can paint your own picture:

This sits on the right of my built-in display all the time. The relevant code for the CPU section is:

${color2}${voffset 5}Intel® i-7 3630QM 3.4 GHz: ${color1}@  ${color green}${freq} MHz   

${color}${goto 13}CPU 1 ${goto 81}${color green}${cpu cpu1}% ${goto 131}${color3}${cpubar cpu1 18}

${color}${goto 13}CPU 2 ${goto 81}${color green}${cpu cpu2}% ${goto 131}${color3}${cpubar cpu2 18}

${color}${goto 13}CPU 3 ${goto 81}${color green}${cpu cpu3}% ${goto 131}${color3}${cpubar cpu3 18}

${color}${goto 13}CPU 4 ${goto 81}${color green}${cpu cpu4}% ${goto 131}${color3}${cpubar cpu4 18}

${color}${goto 13}CPU 5 ${goto 81}${color green}${cpu cpu5}% ${goto 131}${color3}${cpubar cpu5 18}

${color}${goto 13}CPU 6 ${goto 81}${color green}${cpu cpu6}% ${goto 131}${color3}${cpubar cpu6 18}

${color}${goto 13}CPU 7 ${goto 81}${color green}${cpu cpu7}% ${goto 131}${color3}${cpubar cpu7 18}

${color}${goto 13}CPU 8 ${goto 81}${color green}${cpu cpu8}% ${goto 131}${color3}${cpubar cpu8 18}

${color1}All CPU ${color green}${cpu}% ${goto 131}${color1}Temp: ${color green}${hwmon 2 temp 1}°C ${goto 250}${color1}Up: ${color green}$uptime

If you are using an embedded ARM device (such as a Raspberry or ARM based phones), you will not be able to use solutions using lscpu, dmidecode or /proc/cpuinfo because the current speed is not listed there, if the tool is at all available. Instead you have to use sysfs:

alias getcpuf='i=1; for x in $(sudo cat /sys/devices/system/cpu/cpu*/cpufreq/cpuinfo_cur_freq); do y=$(($x/1000)); echo "CPU-${i}: $y MHz"; i=$((i+1)); done;'



# getcpuf

CPU-1: 600 MHz

CPU-2: 600 MHz

CPU-3: 600 MHz

CPU-4: 600 MHz

In a terminal, enter:

cat /proc/cpuinfo | grep name

It should display the exact model of your CPU.

This Wikipedia page on the Sempron will give you detailed specifications.

Here is a straightforward way to get cpu frequencies for all CPU threads:

1. Be sure that cpufrequtils is installed.



2. 
   

   Then in a terminal, run the following command:

   
   
   

   cpufreq-info | grep "frequency is"
   
   

   
   

I wanted to share this as a comment, but dont have many reputations on askubuntu, People who want to use indicator-cpufreq do not need to reboot the computer. Resetting the current X session is enough to display the icon.

sudo apt-get install indicator-cpufreq   

DISPLAY=:0 compiz --replace

You can validate the Performance and Powersave option by seeing the current frequency by

watch -d "cat /proc/cpuinfo | grep -i Mhz"

As soon as you click on a lower frequency / Powersave, the powermanagement of the CPU kicks in, thereby reducing the clock cycle.

Sample output of cat /proc/cpuinfo

processor   : 0

vendor_id   : GenuineIntel

cpu family  : 6

model       : 69

model name  : Intel(R) Core(TM) i7-4500U CPU @ 1.80GHz

stepping    : 1

microcode   : 0x17

cpu MHz     : 774.000

cache size  : 4096 KB

physical id : 0

siblings    : 4

core id     : 0

cpu cores   : 2

apicid      : 0

initial apicid  : 0

fpu     : yes

fpu_exception   : yes

cpuid level : 13

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 pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 fma cx16 xtpr pdcm pcid sse4_1 sse4_2 movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid

bogomips    : 3591.40

clflush size    : 64

cache_alignment : 64

address sizes   : 39 bits physical, 48 bits virtual

power management:



processor   : 1

vendor_id   : GenuineIntel

cpu family  : 6

model       : 69

model name  : Intel(R) Core(TM) i7-4500U CPU @ 1.80GHz

stepping    : 1

microcode   : 0x17

cpu MHz     : 1600.000

cache size  : 4096 KB

physical id : 0

siblings    : 4

core id     : 0

cpu cores   : 2

apicid      : 1

initial apicid  : 1

fpu     : yes

fpu_exception   : yes

cpuid level : 13

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 pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 fma cx16 xtpr pdcm pcid sse4_1 sse4_2 movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid

bogomips    : 3591.40

clflush size    : 64

cache_alignment : 64

address sizes   : 39 bits physical, 48 bits virtual

power management:



processor   : 2

vendor_id   : GenuineIntel

cpu family  : 6

model       : 69

model name  : Intel(R) Core(TM) i7-4500U CPU @ 1.80GHz

stepping    : 1

microcode   : 0x17

cpu MHz     : 800.000

cache size  : 4096 KB

physical id : 0

siblings    : 4

core id     : 1

cpu cores   : 2

apicid      : 2

initial apicid  : 2

fpu     : yes

fpu_exception   : yes

cpuid level : 13

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 pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 fma cx16 xtpr pdcm pcid sse4_1 sse4_2 movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid

bogomips    : 3591.40

clflush size    : 64

cache_alignment : 64

address sizes   : 39 bits physical, 48 bits virtual

power management:



processor   : 3

vendor_id   : GenuineIntel

cpu family  : 6

model       : 69

model name  : Intel(R) Core(TM) i7-4500U CPU @ 1.80GHz

stepping    : 1

microcode   : 0x17

cpu MHz     : 774.000

cache size  : 4096 KB

physical id : 0

siblings    : 4

core id     : 1

cpu cores   : 2

apicid      : 3

initial apicid  : 3

fpu     : yes

fpu_exception   : yes

cpuid level : 13

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 pdpe1gb rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf eagerfpu pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 fma cx16 xtpr pdcm pcid sse4_1 sse4_2 movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm ida arat epb xsaveopt pln pts dtherm tpr_shadow vnmi flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid

bogomips    : 3591.40

clflush size    : 64

cache_alignment : 64

address sizes   : 39 bits physical, 48 bits virtual

power management:

Here cpu MHz means current cpu frequency.
You can run cpufreq-info to understand easily.

In a Linux terminal type the following command to get the CPU core name and it's current speed:

cat /proc/cpuinfo | grep -E "model name|cpu MHz"

sudo powertop then hit Tab twice to get to the "Frequency stats" tab.

It displays Actual frequency (accurate on my Laptop, as opposed to dmidecode), along with stats about how long is spent in each available frequency.

This is my favorite:

watch -n1 "cat /proc/cpuinfo | grep 'MHz'"

Although if you have Turbo Boost (or Turbo Core if AMD), you'll probably prefer:

sudo watch -n 1 -d cpupower monitor

which uses cpupower from the linux-tools group.