Hi, Sergi Barroso wrote: > I'm the author of this blog, I'm using linux-phc to reduce voltage of CPU > frequencies. > > Frequency policy from kernel or userspace only modify frequency/voltage from > core specs, with phc you can use your voltages (under your resposability). > > But it works :)
Does it really? According to the dual core discussion on the website of linux-PHC, the formula the phc uses to estimate the voltage does not work with the dual core processor. I tested it myself and if you apply the formula they use for the dual core and calculate the new voltage, the dual core runs at 950mV with 1000mhz. According to the same website, that is the lowest possible voltage for the dual core processor and that matches with my observations. If I use the values of your blog, the 700 is really 950 and that is what the cpu runs at anyways so the power consumption does not decrease (at least at the 1000mhz step, it might well do so in higher frequencies). That's what I found so I discarded the whole thing as useless. correct me if I am wrong though. all the best, david Here is the referenced discussion: https://www.dedigentoo.org/trac/linux-phc/wiki/IntelCoreLimitationsOfLinuxPHC0_2_X According to my linuxsmc values, the power consumption is the same with or without the phc modes: [EMAIL PROTECTED]:~$ cat /proc/acpi/battery/BAT0/state present: yes capacity state: ok charging state: charged present rate: 0 mW remaining capacity: 39300 mWh present voltage: 12570 mV [EMAIL PROTECTED]:~$ cat /proc/acpi/battery/BAT0/state present: yes capacity state: ok charging state: charged present rate: 0 mW remaining capacity: 39300 mWh present voltage: 12571 mV [EMAIL PROTECTED]:~$ cat /proc/acpi/battery/BAT0/state present: yes capacity state: ok charging state: charged present rate: 0 mW remaining capacity: 39300 mWh present voltage: 12571 mV [EMAIL PROTECTED]:~$ cat /sys/devices/system/cpu/cpu?/cpufreq/op_points_table 2000000:1404,1833000:1340,1667000:1276,1500000:1212,1333000:1148,1000000:1004 2000000:1404,1833000:1340,1667000:1276,1500000:1212,1333000:1148,1000000:1004 homeless:/home/david# echo 2000000:1404,1833000:1240,1667000:1176,1500000:1112,1333000:1048,1000000:700 > /sys/devices/system/cpu/cpu0/cpufreq/op_points_table homeless:/home/david# echo 2000000:1404,1833000:1240,1667000:1176,1500000:1112,1333000:1048,1000000:700 > /sys/devices/system/cpu/cpu1/cpufreq/op_points_table [EMAIL PROTECTED]:~$ cat /proc/acpi/battery/BAT0/state present: yes capacity state: ok charging state: charged present rate: 0 mW remaining capacity: 39300 mWh present voltage: 12570 mV ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Mactel-linux-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mactel-linux-users
