J5005 does not downclock to baseclock

[mgutt]

I have two unraid servers. One uses an Atom C3758 CPU. After installing the Tips and Tweaks Plugin and changing from On Demand to Power Save it downclocks to 800 Mhz as expected. The other server uses a Pentium J5005. The dashboard returns most of the time a usage of 0-2% for all cores:

 

By using this command in the web terminal:

watch grep \"cpu MHz\" /proc/cpuinfo

 

it returns 2.3 Ghz:

Every 2.0s: grep "cpu MHz" /proc/cpuinfo                                                     Black: Mon Jun 15 00:03:51 2020

cpu MHz         : 2399.270
cpu MHz         : 2315.888
cpu MHz         : 2088.474
cpu MHz         : 2333.949

 

After disabling the Intel Turbo it returns 1.3 GHz:

Every 2.0s: grep "cpu MHz" /proc/cpuinfo                                                     Black: Mon Jun 15 00:07:02 2020

cpu MHz         : 1318.495
cpu MHz         : 1342.343
cpu MHz         : 1245.570
cpu MHz         : 1369.103

It clocks now under the baseclock (1.5 Ghz) of this CPU?!

 

But the real strange thing is the power consumption as its nearly the same for all settings (all five disks spun down):

 

Performance + Turbo: 18.59W

Power Save + Turbo: 18.09W

Power Save: 18.09W

Power Save + Closed all browser windows: 18.02W

 

Power measurement was done with a good consumer power meter (<5W +/- 100mW and >5W +/- 2%).

 

EDIT: Hmm I restarted the server and altough the Tips and Tricks plugin displays "Power Save" its in "Performance" mode (as all cores stay at 2.6GHz).

Edited June 15, 2020 by mgutt