Joined: 13 Mar 2008
|Posted: Fri Apr 15, 2016 8:29 pm Post subject: Haswell package never goes lower than PC3
|I run Thinkpad T540p with i7-4700MQ. Kernel is gentoo-sources-4.5.1. The minimal power consumption I've seen is 14.4 W. I started to find out...
I've installed i7z-git and discovered that my cores are in C7 >90% of time when my PC is idle (only Gnome 3.18 shell is running)
I've installed powertop-9999 and in the idle stats I can see that core states match the data from i7z.
However the package states are like this:
|C2 (pc2) 49,5%
C3 (pc3) 7,0%
C6 (pc6) 0,0%
C7 (pc7) 0,0%
I have tlp installed and running. It's doing a good job clocking down my CPU and managing other devices' power.
I've never seen my CPU package drop to PC6 or PC7. I think this is the main reason why my idle power consumption is so high.
What can I do to lower by CPU power?