I'm trying to get the CPU frequency up to 2.24 Ghz on the Advanced board. I've got Ubuntu 16.04 installed along with cpufrequtils package. I also have custom active cooling on my boards (current CPU stress tests stay under about 51c so it seems like it could handle a higher frequency). I first tried setting the performance governor: Code: ubuntu@udoo1:~$ sudo cpufreq-set -r -g performance But no go: Code: ubuntu@udoo1:~$ sudo cpufreq-info cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to cpufreq@vger.kernel.org, please. analyzing CPU 0: driver: intel_pstate CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 0.97 ms. hardware limits: 480 MHz - 2.24 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 480 MHz and 1.79 GHz. The governor "performance" may decide which speed to use within this range. current CPU frequency is 1.76 GHz (asserted by call to hardware). Setting the speed manually doesn't seem to affect it either: Code: ubuntu@udoo1:~$ sudo cpufreq-set -r -u 2.24Ghz ubuntu@udoo1:~$ sudo cpufreq-info cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to cpufreq@vger.kernel.org, please. analyzing CPU 0: driver: intel_pstate CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 0.97 ms. hardware limits: 480 MHz - 2.24 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 480 MHz and 1.79 GHz. The governor "performance" may decide which speed to use within this range. current CPU frequency is 1.76 GHz (asserted by call to hardware). I also tried disabling intel_pstate: Code: ubuntu@udoo1:~$ cat /proc/cmdline BOOT_IMAGE=/vmlinuz-4.10.0-38-generic root=/dev/mapper/udoo1--vg-root ro intel_pstate=disable quiet splash vt.handoff=7 But it results in even lower default frequencies: Code: ubuntu@udoo1:~$ sudo cpufreq-info cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to cpufreq@vger.kernel.org, please. analyzing CPU 0: driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 10.0 us. hardware limits: 480 MHz - 1.60 GHz available frequency steps: 1.60 GHz, 1.60 GHz, 1.52 GHz, 1.44 GHz, 1.36 GHz, 1.28 GHz, 1.20 GHz, 1.12 GHz, 1.04 GHz, 960 MHz, 880 MHz, 800 MHz, 720 MHz, 640 MHz, 560 MHz, 480 MHz available cpufreq governors: conservative, ondemand, userspace, powersave, performance, schedutil current policy: frequency should be within 480 MHz and 1.28 GHz. The governor "ondemand" may decide which speed to use within this range. current CPU frequency is 1.28 GHz (asserted by call to hardware). cpufreq stats: 1.60 GHz:4.57%, 1.60 GHz:0.00%, 1.52 GHz:0.00%, 1.44 GHz:0.00%, 1.36 GHz:0.00%, 1.28 GHz:47.17%, 1.20 GHz:0.03%, 1.12 GHz:0.04%, 1.04 GHz:0.03%, 960 MHz:0.08%, 880 MHz:0.80%, 800 MHz:0.10%, 720 MHz:0.21%, 640 MHz:0.34%, 560 MHz:2.55%, 480 MHz:44.10% (107) After some more digging I found the pstate sysfs settings. There seems to be a max scaling percentage locked at 80%: Code: ubuntu@udoo1:~$ echo 100 | sudo tee /sys/devices/system/cpu/intel_pstate/max_perf_pct 100 ubuntu@udoo1:~$ cat /sys/devices/system/cpu/intel_pstate/max_perf_pct 80 So, is there a way to get Ubuntu running at full 2.24GHz clock?
This has been discussed before, and there doesn't seem to be any way to use full speed. For some reason e.g. Ubuntu and Debian limit speed to about 80% of maximum.
Intel ATOM CPU's burst mode is set in CPU manufacturing process and is locked. It is neither the overclock or performance governor-controlled. See this general info to get a peek inside... http://download.intel.com/newsroom/kits/mobileworld/2013/pdfs/Intel_Atom_Processors_Brief.pdf
Does that mean that it also runs at 1.76 GHz on other operating systems (such as Windows) as well? If it is actually locked to 1.76 on the CPU then why is it advertised as 2.24 GHz? Under what conditions can it reach 2.24 GHz?
In all operating systems. 2.24 is a marketing gimmick. Intel never disclosed exactly on what conditions will trigger the up-speed but we know it's very brief (so it won't kill the higher priced CPU tier) and it does want to "return to normal" ASAP. After all, ATOM family is extremely cheap (is there to compete with ARM) and supposed to be low heat generated (fanless is the ultimate goal) and low power consumption. For example, the latest ATOM gen upgrade, the server class and desktop class are essentially cancelled. Gap in between the low-tier high-grade and mid-tier low grade is getting too close. Volume pricing on ATOM can be very, very low (say less than $20 for the entire system SoC), while Pentium is about $40 and up and i3 is close to a 3-digit figure.
