Warning: as of yet, there is no official support for overclocking the Raspberry Pi 3, so you could damage your small computer. Just a reminder…
This is the settings in /boot/config.txt for the overclocking part.
# Overclocking arm_freq=1500 sdram_freq=550 over_voltage=6 temp_limit=85 #Will throttle to default clock speed if hit.
Running the command
sysbench --num-threads=4 --test=cpu --cpu-max-prime=2000000 run
for over an hour, the temperature never exceeds 65 C° and this while at the same time playing 24-bit 192KHz audio. This is a Raspberry Pi 3 mounted inside a box with a DAC card added on top! I’ve waited two month before writing this up, because I wanted to make sure it would work in the long run. It’s now been running continuously now without any glitches. So the next step is to try the same thing on my NTP server. That Raspberry Pi 3 is mounted in my 3D printed box with a fan, so it’s going to be interesting to find out if I can go higher than 1350MHz that it’s currently running at. Hoping for 1.5GHz on this one as well naturally…
I wrote a small shell script to monitor the CPU speed and the temperature to be able to see if it gets to hot during my experiments.
I created a file called check_cpu_speed_temp.sh
cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq /opt/vc/bin/vcgencmd measure_temp
Run the testing with following command:
chmod +x check_cpu_speed_temp.sh watch ./check_cpu_speed_temp.shYou will see result similar like following:
Every 2.0s: ./check_cpu_speed_temp.sh Thu Feb 9 05:04:12 2017 1400000 temp=82.7'C