Cool 'n' Quite is an energy efficient technology for AMD k8 and K10 or above series of processor, Few of the distro like Ubuntu comes with all the tweaks and utilities needed to enable Cool n Quite but some don't, CnQ reduce the multiplier and substantially reducing the speed saving lot of power and keep the PC cool if you are aiming for prolong use.
First we will check whether it is working or not. To test it just run
Code:
cat /proc/cpuinfo or run lshw as super user.If the program shows full speed of CPU then the Energy efficient technology is not working.
To enable we have to first install cpufreq . Install it from the package manager and reboot.
Now check cpufreq file exist or not.
Code:
cat /etc/sysconfig/cpufreqThe output should be something like this
Code:
# set cpufreq governor if defined
# possible choices are: ondemand powersave userspace performance
GOVERNOR=ondemand
# minimum frequency
#MIN_FREQ=
# maximum frequency
#MAX_FREQ=
# Uncomment to use acpi-cpufreq as fallback
#USE_ACPI_CPUFREQ=yesIf you want Cool n Quite, either change the GOVERNOR to Ondemand or Powersafe .
Now we have to check that cpufreq has created a file under modprobe directory or not. If not open the files as root ,
Code:
kwrite /etc/modprobe.preload.d/cpufreqChange kwrite with gedit or any other text editor that you use. Copy the following content and save it
Code:
powernow-k8
cpufreq_performance
cpufreq_powersave
cpufreq_conservative
cpufreq_ondemandWe have done enabling the Amd Cool n Quite. Just reboot the system and run
Code:
/cat/proc/cpuinfo or lshw as root to confirm it.The new speed should be less than half of the current speed. To revert back just change the GOVERNOR to Performance in /etc/sysconfig/cpufreq and it will change back to normal.
This is what my cpuinfo looks like after enabling Cool 'n' Quite
Code:
[shashwat@localhost ~]$ cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 16
model : 4 [B]
model name : AMD Phenom(tm) II X4 B50 Processor
stepping : 2
cpu MHz : 800.000
cache size : 512 KB [/B]
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
initial apicid : 0
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc nonstop_tsc pni monitor cx16 lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt
bogomips : 6200.42
clflush size : 64
power management: ts ttp tm stc 100mhzsteps hwpstate
processor : 1
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Phenom(tm) II X4 B50 Processor
stepping : 2
cpu MHz : 800.000
cache size : 512 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 1
initial apicid : 1
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc nonstop_tsc pni monitor cx16 lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt
bogomips : 6200.39
clflush size : 64
power management: ts ttp tm stc 100mhzsteps hwpstate
processor : 2
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Phenom(tm) II X4 B50 Processor
stepping : 2
cpu MHz : 800.000
cache size : 512 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 3
initial apicid : 3
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc nonstop_tsc pni monitor cx16 lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt
bogomips : 6200.39
clflush size : 64
power management: ts ttp tm stc 100mhzsteps hwpstate
processor : 3
vendor_id : AuthenticAMD
cpu family : 16
model : 4
model name : AMD Phenom(tm) II X4 B50 Processor
stepping : 2
cpu MHz : 800.000
cache size : 512 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 2
initial apicid : 2
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 3dnowext 3dnow constant_tsc nonstop_tsc pni monitor cx16 lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt
bogomips : 6200.39
clflush size : 64
power management: ts ttp tm stc 100mhzsteps hwpstate
[shashwat@localhost ~]$You can also use Gnome freq scaling applet for doing this if all the above files are updated
KDE has powerdevil but that is only applicable for mobile cpus at the most.Please digg the tutorial here : http://digg.com/linux_unix/Tutorial_Enable_AMD_Cool_n_Quite_in_Linux
Hope you like the tutorial
Regards
