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Raspberry Pi 3 Overclocking

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Raspberry-Pi-3-boxWarning: as of yet, there is no official support for overclocking the Raspberry Pi 3, so you could damage your small computer. Just a reminder.

Update: I’ve managed to make a DIY heatsink for the Raspberry Pi 3 for $4, and it’s running stable at 1.5GHz. Click here to read.

The new version of Raspberry Pi 3 was released yesterday, so I naturally had to get two. I’m using two as Stratum-1 NTP servers, and with the old Raspberry Pi 2, I had hit the roof when it came down to getting better time resolution. So when I read that a new 50% faster version had been released, I raced to the nearest store and got a couple. I have one experimental NTP server that isn’t handing out time on the internet and another one that is the primary server, connected to the NTP Pool Project.

I installed the experimental Raspberry Pi 3 first, so I could test performance and try to overclock it. And it went very well.

Overclocking

Raspberry-Pi-3-cpu-heatsinkNaturally, I want to get the most out of the Raspberry Pi 3, so I got some small heat sinks. There’s one larger for the CPU/GPU, so that was easy enough. But then it got confusing. What to do with the other two smaller heatsinks included in the “overclock kit” for the Raspberry Pi. The immediate instinct is to put it on the other large IC, but after searching for SMSC LAN9514 I realized it was the controller for Ethernet and USB and had a hard time trying to understand why the Internet was full of pictures of people putting a heatsink on a network/USB controller. I wanted to overclock the processor and memory. The memory chip is on the underside of the board, so I decided to put both of the smaller heatsinks on the SDRAM instead. Seems to me to be a better place to put a heatsink. But It comes with a problem. Space. Most enclosures for the Raspberry Pi doesn’t have enough room for heatsinks on the bottom side of the card. Fortunately, my board uses spacers, so I could use longer standoffs and fit the board correctly, even putting a wee bit of pressure on the heatsinks to help with the cooling.

Raspberry-Pi-3-heatsink-memory

Overclock Testing

Time to fire the new Raspberry Pi 3 up and try to get the max performance out of it. I booted it with the already installed Linux Raspian, and all worked as normal, just…you know, faster. Time to test. First I put the CPU cores in “Performance” mode so they wouldn’t go down to a slower speed. A Raspberry Pi have different CPU modes like conservative, on demand, userspace, power save and performance. When the processor has a light load, it goes into power saving mode, that switches to a lower CPU speed. So I put all the CPU cores in performance mode by writing the following command line.

echo "performance" |sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

I wrote a small shell script to monitor the CPU speed and the temperature to be able to see if it gets too hot during my experiments.
I created a file called check_cpu_speed_temp.sh

pico check_cpu_speed_temp.sh

and wrote:

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
/opt/vc/bin/vcgencmd measure_temp

Now it was time to try how much I could overclock it. I opened the config.txt file in the /boot/ directory and changed the arm_freq setting to:

arm_freq=1400

I rebooted and everything looked good. So to test if the Raspberry Pi 3 would be stable under heavy load I wrote this on the command line, just to get the cores working at 100% CPU usage:

fulload() { dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null & }; fulload

This just creates four threads that copies zeros into /dev/null, the linux equivalent of a digital trashcan. This puts all four cores at close to 100% all the time.
I started the small shell script, having it update every two seconds by writing:

watch ./check_cpu_speed_temp.sh

And watched as the temperature climbed. It stopped around 58-59 °C and stayed there. The next step, going up to 1.45 GHz didn’t work, the machine refused to boot. So I put the SD-card in my Macbook Pro and edited the /boot/config.txt, adding voltage boost by adding the line:

arm_freq=1400
over_voltage=6

Now the machine booted up without a problem. I managed to run the Raspberry Pi 3 at 1.5 GHz but decided not to overdo it. I compromised and settled on a CPU frequency of 1.45 GHz.

If you want to kill the processes that bog down the CPU, just write killall dd and they will stop.
Raspberry-Pi-3-temp-cpu

Memory Overclocking

Next step, overclock the memory speed. It seems like the new Raspberry Pi 3 has the same SDRAM memory as the Raspberry Pi 2. The standard rate is 400 MHz. I tried to bump it up, but it maxed out at 500 MHz. So I added sdram_freq=500 in /boot/config.txt. It worked perfectly. Next up was 550, but then the machine got unstable, so I settled for 500.

Graphics

I haven’t tried to increase the speed of the GPU. My Raspberry Pi runs as a headless server, but I realize that the GPU speed is connected to the speed of the L2 cache, so maybe this is something to experiment with at a later time. Raspberry Pi 2 and newer have separate L2 Cache between CPU and GPU.

Running Your Raspberry Pi 3 at Full Speed All The Time

If you add the following two lines, your Raspberry Pi 3 will run at full speed all the time. Doing this will guarantee that you’re violating your warranty if something goes wrong. Just a warning.

force_turbo=1

boot_delay=1

Not all Raspberry Pi 3 are created equal

So I now had a Raspberry Pi 3 that run with 1000 MHz more combined processing power than the standard one and with a speed boost of the SDRAM. Naturally, I had to try it out on my other unit. No such luck. As soon as I tried to increase the CPU speed, it quickly climbed to over 80 °C and became unstable. So It seems like you have to cross your fingers when it comes to the possibility to overclock your Raspberry Pi 3. I quickly moved the faster card to my main server, because it is the one that needs the most speed.

Is the Raspberry Pi 3 faster?

I’m running the two Raspberry Pi as NTP-servers. Here’s a before-after plot of the time resolution on my Stratum-1 NTP-server loopback statistics.

ntp-offsets-Raspberry-Pi-3

Nano Second Raspberry Pi 3 NTP Server

The servers precision has gone from 0.95367431640625 µS calculated precision to 0.476837158203125 µS. So I’m now in the nanoSecond territory on my Stratum-1 NTP-server. Unfortunately, the Raspberry Pi’s Ethernet goes through USB at 100Mbit/sec, so that’s a bottleneck.

The overclocked Raspberry Pi 3 has now been running for 24 hours, handing out time to thousands of computers and it is stable as a rock. Update 2016-03-16: Still running one of the Raspberry Pi 3’s at 1350 MHz and 500 MHz memory settings and it’s rock solid.

So it seems like it’s a crap shoot if you’re going to be able to overclock your Raspberry Pi 3. I got lucky with one of the cards. And let’s face it, a 1.2 Quad Core 64-bit computer for $40 is fantastic!

Benchmarking the Overclocked Raspberry Pi 3

After comments about the overclocking not working, here are my results. The test program seems to be a single thread, but I can debunk the idea of the processor going slower when overclocking.

Standard Raspberry Pi 3 – no overclocking



BYTEmark* Native Mode Benchmark ver. 2 (10/95)

Index-split by Andrew D. Balsa (11/97)

Linux/Unix* port by Uwe F. Mayer (12/96,11/97)



TEST                : Iterations/sec.  : Old Index   : New Index

                    :                  : Pentium 90* : AMD K6/233*

--------------------:------------------:-------------:------------

NUMERIC SORT        :          650.05  :      16.67  :       5.48

STRING SORT         :          66.218  :      29.59  :       4.58

BITFIELD            :      1.8311e+08  :      31.41  :       6.56

FP EMULATION        :          124.03  :      59.52  :      13.73

FOURIER             :          6531.7  :       7.43  :       4.17

ASSIGNMENT          :          8.6217  :      32.81  :       8.51

IDEA                :          1858.7  :      28.43  :       8.44

HUFFMAN             :          896.88  :      24.87  :       7.94

NEURAL NET          :          9.7445  :      15.65  :       6.58

LU DECOMPOSITION    :          314.82  :      16.31  :      11.78

==========================ORIGINAL BYTEMARK RESULTS==========================

INTEGER INDEX       : 29.905

FLOATING-POINT INDEX: 12.378

Baseline (MSDOS*)   : Pentium* 90, 256 KB L2-cache, Watcom* compiler 10.0

==============================LINUX DATA BELOW===============================

CPU                 : 4 CPU ARMv7 Processor rev 4 (v7l)

L2 Cache            : 

OS                  : Linux 4.1.17-v7-atom-pps+

C compiler          : gcc version 4.9.2 (Raspbian 4.9.2-10) 

libc                : libc-2.19.so

MEMORY INDEX        : 6.347

INTEGER INDEX       : 8.426

FLOATING-POINT INDEX: 6.865

Baseline (LINUX)    : AMD K6/233*, 512 KB L2-cache, gcc 2.7.2.3, libc-5.4.38

* Trademarks are property of their respective holder.

Overclocked Raspberry Pi 3 to 1350 MHz CPU and 500 MHz SDRAM clock speed



BYTEmark* Native Mode Benchmark ver. 2 (10/95)

Index-split by Andrew D. Balsa (11/97)

Linux/Unix* port by Uwe F. Mayer (12/96,11/97)



TEST                : Iterations/sec.  : Old Index   : New Index

                    :                  : Pentium 90* : AMD K6/233*

--------------------:------------------:-------------:------------

NUMERIC SORT        :          685.76  :      17.59  :       5.78

STRING SORT         :          68.556  :      30.63  :       4.74

BITFIELD            :      1.9658e+08  :      33.72  :       7.04

FP EMULATION        :          129.07  :      61.93  :      14.29

FOURIER             :          6460.8  :       7.35  :       4.13

ASSIGNMENT          :          10.302  :      39.20  :      10.17

IDEA                :          1972.1  :      30.16  :       8.96

HUFFMAN             :          930.43  :      25.80  :       8.24

NEURAL NET          :          10.065  :      16.17  :       6.80

LU DECOMPOSITION    :          400.31  :      20.74  :      14.97

==========================ORIGINAL BYTEMARK RESULTS==========================

INTEGER INDEX       : 31.995

FLOATING-POINT INDEX: 13.506

Baseline (MSDOS*)   : Pentium* 90, 256 KB L2-cache, Watcom* compiler 10.0

==============================LINUX DATA BELOW===============================

CPU                 : 4 CPU ARMv7 Processor rev 4 (v7l)

L2 Cache            : 

OS                  : Linux 4.1.17-v7-atom-pps+

C compiler          : gcc version 4.9.2 (Raspbian 4.9.2-10) 

libc                : libc-2.19.so

MEMORY INDEX        : 6.977

INTEGER INDEX       : 8.834

FLOATING-POINT INDEX: 7.491

Baseline (LINUX)    : AMD K6/233*, 512 KB L2-cache, gcc 2.7.2.3, libc-5.4.38

* Trademarks are property of their respective holder.

Comments

  1. It sounds like your Raspberry Pi heatsink kit was designed for the Raspberry Pi 1.

    The SMSC USB hub+Ethernet chip used to get very hot because of a wiring mistake on the original RPi 1 which is why people started putting heatsinks on it. When designing the board, they misconnected the output of a 1.8V regulator built into the USB chip to the SoC + 1.8V linear regulator (RG1) on the board. If the USB chip regulator output was slightly higher due to normal variation than the board linear regulator then the SMSC chip would end up powering the SoC as well.

    The remaining small heatsink was for 3.3V linear regulator (RG2) on the Raspberry Pi 1 board which has since been replaced with a far more efficient SMPS design.

    No real reason to put a heatsink on the SMSC chip now though since a properly wired board has the SMSC chip running cool.

    Reply

  2. I’d like to know how much you could overclock the “bad overcloker” Pi 3 board before running into problems. The Pi 2 is known to go up to 1150Mhz… but the majority of the boards aren’t really stable after 1050/1000Mhz.

    It would be nice to know what the “overclock baseline” with the Pi 3 would be.

    Reply

    • My thoughts as well. I’m currently working on modifying a lab reference distribution amplifier, but as soon as it is up and running I’m going to continue to explore how much the “bad” version of the boards can take.

      Watch this space for further development…

      🙂

      Reply

      • Well, just a follow up as I now have my own board for little while.

        It seems that my board is stable at 1300 with heavy 4 core workloads and tops at 1350 with 2 core heavy workloads, even when using 6 overvolt.

        Heat doesn’t seem to be the problem as the CPU hangs before even reaching 83 degrees. I used a big heatsink but I doubt using a bigger one or even a fan would improve my overclock results. Maybe with higher overvolt… but I don’t dare anything higher than 6 for now.

        Reply

    • Why? The USB chip gets warm but not hot enough that it actually needs a heatsink. The chip is rated for far higher temperatures and it isnt throttling throughput due to temperature. You can put one on if you want but it doesn’t do anything useful apart from blinging out your Raspberry Pi.

      Reply

  5. This is a great post. Thank you. I got utterly stuck when rasp-config said I couldn’t overclock my pi 3.

    I’ve managed to get to 1.3ghz and 425mhz (cpu/ram) and be stable. 1.4ghz wouldn’t boot and 450mhz kept causing random lockups. Might be brave and try 1.35ghz on the CPU.

    Wasn’t too keen to increase the voltage, but I bet that would’ve helped, as my temperatures were never a problem. So that’s my experience at least.

    Reply

    • I would go with 1.35 GHz and increase the voltage to 4 or 6. I’ve put my main server down to 1.35 GHz and 6 on over volt, just to be a bit conservative. But hey, if the “magic smoke” escapes, the board doesn’t cost a fortune.

      Reply

      • This pi will probably end up being battery powered, so upping the voltage is not desirable (hell, overclocking probably isn’t a good idea!) but thanks for the input, and this great blog post.

        Reply

  6. I think its not overclockable at this time… You actually downclocked it. But I might be wrong.
    In my testing when running stock I get 1903 in HWbot prime (java based), when I overclock the cpu to 1350mhz I get only 1445 points. But when I overclock the ram and gpu the score stays the same (or even lower at times)… So I guess none of the overclocks are actually working or they have a negative effect on the performance.

    Reply

    • Maybe the cpu frequency is being automatically down-throttled by the excessive heat? I guess that’s the only way your results would make sense.

      Are you using a heatsink?

      Reply

      • Yes I’m using a heat sink. But today I noticed that the score went down to 1350 when @stock after I upgraded the firmware. Then I tried overclocking it and it didn’t really show any improvements… So maybe my Pie its just weird (just like my first RPI B).

        Reply

    • Hi! Thanks for the tip on RPi-Monitor. I’m using my two Raspberry Pi 3’s as NTP-servers. I try to have as little software installed as possible on them because every little process affects the performance of the server timing. But this is good to know for other projects.

      Thanks!

      Jacken

      Reply

  9. My Pi 3 at 1.3ghz with no over volt freezes when like launching Firefox and loading my Twitter timeline. It seems OK at 1.25.

    (It seems to run at least at 1.3 with a bit of overvolt, not sure if it’s stable enough yet…)

    Not too much luck for my Pi 3 i guess…

    Reply

    • Update on my Pi 3… i didn’t test a lot more with o/c, quickly bactracked. I looked at the temps without overclocking or anything else for a while, playing a 480p Youtube video in Firefox (on Ubuntu Mate), the temp quickly reaches 70°C and then quickly after that it reaches 80°C before the end of the 3 minutes trailer i was watching :/ Given the temp protection is at 85°C it doesn’t seem/feel great.

      Reply

  10. Is it possible to kill a RPi3 from overclocking/overvoltage?

    I know Intels and AMDs will protect themselves by automatically lowering their frequency if they get too hot. Will the RPI do the same?

    Reply

    • I actually think so. My second Raspberry Pi 3 is very flaky under heavy load, even when not overclocked. Thinking of buying a third just to try it out (you can never have too many Raspberry Pi’s)

      You should be able to find small heatsinks on eBay.

      PS: I added a warning at the beginning of the post for people to let them know they may void their warranty.

      Reply

      • Hi Sandy,

        I never broke a Raspberry with OC experiments, mostly the poor quality of the switched power supply
        where cause of breaking stuff or corrupting your SD card.

        Invest in a good power supply with current control, because imho is the power supply the most important thing to watch in experiments.

        Reply

  11. Just FYI, upgrading to Debian Jessie and kernel 4.1 will make your test results some 10% better without any overclock. My stock RPi3 results:

    BYTEmark* Native Mode Benchmark ver. 2 (10/95)
    Index-split by Andrew D. Balsa (11/97)
    Linux/Unix* port by Uwe F. Mayer (12/96,11/97)

    TEST : Iterations/sec. : Old Index : New Index
    : : Pentium 90* : AMD K6/233*
    ——————–:——————:————-:————
    NUMERIC SORT : 698.15 : 17.90 : 5.88
    STRING SORT : 69.929 : 31.25 : 4.84
    BITFIELD : 1.9972e+08 : 34.26 : 7.16
    FP EMULATION : 131.22 : 62.97 : 14.53
    FOURIER : 6564.5 : 7.47 : 4.19
    ^C

    Reply

  12. Hi,

    Great post Jack.

    I have tried to oc my Pi3, as described to 1350 and 1400 and to no avail. It boots with any setting changed arm_freq, sdram_freq, core_freq etc.
    Temp stays at ~50oC, all 4 cores run boinc at 100%
    None of it changes the performance, the only benchmark I run is the boinc client Run Benchmark and I always get the same result 376 floating point MIPS and 1240 integer MIPS. This is even slower than my Pi2 oc at 1GHz which gets 498 floating point MIPS and 1898 integer MIPS.

    I’m thinking that the oc is deliberately turned off in the raspbian version I run.

    Any ideas?
    Niels

    Reply

    • Hello Niels,
      I had the same trouble than you, I was ready to send back my four Rpi3 to the vendor, when i tried a bigger electicity source : 3A, and miracle my RPI3 has went 2 time speeder !!!
      So be carefull don’t source your pi with an usb 2 pc port like me !!!!

      Have a good trip !
      RPI is great ! but how strange to moderate speed in function of current !!!
      I hope i help you?

      Reply

  13. I have two Raspberry Pi 3 boards here, both can do 1400mhz but refuse to go any higher. Both tested with OpenELEC.
    One of them has the heatsink on the CPU/GPU and the other is bare. I’m waiting for adhesive thermal pads.

    I wondered what kind of mount/case Jack is using, and if any other cases have space underneath like that?

    Reply

  14. I can highly recommend to but a small mini fan on the SOC, it reduced the max temp by 20°C for me. Take the power from the GPIO.

    Reply

  16. Just a note, you don’t have to do this for every cpu core:

    for gov in /sys/devices/system/cpu/cpu[0-9]*/cpufreq/scaling_governor; do echo “performance” | sudo tee $gov >/dev/null; done

    The file scaling_governor is the same for all cores. In fact the cpufreq subdirectories under cpu1, cpu2 and cpu3 are just symlinks to cpu0/cpufreq.

    So all you really have to do is: echo “performance” |sudo tee /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

    Reply

  17. Jack your script to put all 4 cores at 100% load is severely flawed. According to ‘top’, all cores are only at 30% load (I can get a higher load on all 4 cores simply by watching a youtube video in theatre mode, and a 720p mp4 in omxplayer).
    See; http://s18.postimg.org/i1m98qbih/2016_03_26_121836_1680x1050_scrot.png

    I suggest you put all 4 cores under full 100% load (instead of 4 cores at 30% load), and then see how stable your arm_freq overclock truly is.

    Instead of this:
    fulload() { dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null & }; fulload

    Use this:
    wget https://raw.githubusercontent.com/ssvb/cpuburn-arm/master/cpuburn-a53.S
    gcc -o cpuburn-a53 cpuburn-a53.S
    ./cpuburn-a53

    Reply

    • Weird, because I used top to check hand get from 96-100% utilisation of the CPU cores. But if you have a better solution, run with it. I have statistics that plot a lot of data every hour, so all the cores are at 100% for six minutes every hour. At 1350 MHz it’s still running without a problem for three weeks.

      Reply

  19. These are the settings I am using on my Pi3 to fully optimize it:

    # Uncomment to overclock ARMv8 (Cortex-A53) CPU (1200 MHz); DDR2-800 SDRAM (450 MHz);
    # VideoCore IV GPU (300 GHz); double read/write performance of UHS-1/HC-1 SD Card;
    # and set memory allocation of 1GB LPDDR2 SDRAM for VideoCore IV GPU
    dtparam=sd_overclock=100
    arm_freq=1300
    core_freq=500
    over_voltage=4
    sdram_freq=575
    sdram_schmoo=0x02000020
    over_voltage_sdram_p=6
    over_voltage_sdram_i=4
    over_voltage_sdram_c=4
    v3d_freq=500
    h264_freq=333
    gpu_mem=256

    Reply

  20. When mentioning operating temperatures, could you, please, mention the ambient temperature, also. It is important to know this since not everyone is in Sweden or Canada 🙂 Thank you

    Reply

  21. I am testing the temperatures, standard RPI 3 settings, full load and without head sink the temperature is 80,4 °C in house is the temperature about 20 °C. Temperature with head sink is 78,4 °C only 2 ° C lower, then I put on top of the head sink a bigger one 5 x 5 x 4 cm then the temperature go down to 68.8 ° C so 12 °C lower and the connection between the two head sinks is not optimal, because the two head sinks are on top of each.

    Conclusion, you need a bigger head sink and the original is as good as useless, only 2° C difference. Second conclusion, I think that you can select the boards by measuring the temperature. A Board with a lower temperature on full load, will have also a lower temperature with overclocking and must be more stable.

    suggestions, head sinks etc…

    Reply

    • This is good information. So the temperature rise, with a “beefy” heat sink is as much as 48-49 Celcius. One thing that would be, also, very valuable is the time it takes to reach a steady state temperature; i.e. did you run the test long enough for the temperature to stabilize for at least ten minutes and how long was the total run?
      Thank you

      Reply

      • Hello, Demi
        With a decent heat sink the temperature wil rise indeed about 50 ° C full load operation and no overclocking. The time delay is very short, more seconds, with an stabilization after five to ten minutes.
        Without full load, internet and so on, the temperature is between 44 °C an 50 °C without the big heat sink.
        With normal use without overclocking you don’t need an head sink at all, because the temperature wsil be between 44° C and 80 °C in case of full load.
        I think with overclocking the temperature and full load the temperature will go over 100 ° C but mostly you don’t go for full load, so the temperature will stay lower, but I fond out that the temperature can go up in seconds, this mean that a short full load can heat up the chip en make it unstable.
        In this case you need a big head sink, the small one is useless. With the small one te temperature drops only 2-3 °C.
        From board to board there could be a difference, so therefore you can select the board’s by measuring the temperature in normal mode and choose those boards to overclock with the lowest normal full load working temperature.
        Mow I am looking for a bigger head sink or an adaption, and some kind of heat conducting glue

        Reply

      • There is other thing, with a heat sink the rise of the temperature is slower due to the heat capacity of the heat sink itself. It works as a buffer, so even if a small heat sink will not cool enough, it will smooth the temperature changes. so it go from seconds up to one minute, and of course with a bigger head sink the changes are also more smooth than than with the smaller one.

        Reply

  22. sweet spot for me on my RPi3 is:

    arm_freq=1350
    over_voltage=5

    very nice! i use a heatsink on the CPU…

    i’m getting ready to stress-test a 3rd RPi with a heat sink and 5V fan next week…

    willie ‘I love the smell of napalm in the morning’ on the Gulf of Mexico

    Reply

  23. This is my third Raspberry Pi 3. The three of them failed to pass sudo memtester 128M with config.txt untouched in latest raspbian installed from Noobs . Only when I force sdram to a 400 MHz the raspberry passes the test without failure. I’m desperate.
    I use a pc fan that keeps temperatures under 45 ºC when running memtester. When I run a sysbench with 4 threads to force 100 % load the temperature never goes higher than 62ºC and consequently doesn’t throttle.

    Reply

    • “…three of them failed to pass sudo memtester 128M with config.txt untouched in latest raspbian installed from Noobs”

      You realize that isn’t how you are supposed to use Memtester? You are actually only testing 128 MB out of 1 GB, and you don’t run it as ‘sudu’ in any event.

      Lower gpu memory to 64 ( ‘gpu_mem=64’), then test as much memory as you can for multiple passes:

      memtester 700m 5

      Reply

  24. There is a new benchmark for the Pi 3 that will tell you if your overclock is stable (Linpack Bench). An unstable overclock, or improperly powered or cooled Pi 3 will perform poorly on the benchmark, or will outright fail it. The test takes approx 2 min to run or so.

    A stock Pi 3 can pass the bench at 6 Gflops (Processor performance of 6 billion operations per second), a moderately overclocked Pi 3 (1275 MHz and with over_voltage=6), can pass the benchmark at 6.8 Gflops.

    Video: https://youtu.be/KuEZV0WsRLg?t=18m43s

    Install and run Linpack (be sure to reboot after install, and prior to benchmark run):

    Install Linpack:
    sudo apt-get install libmpich-dev
    wget http://web.eece.maine.edu/~vweaver/junk/pi3_hpl.tar.gz
    tar -xvzf pi3_hpl.tar.gz
    chmod +x xhpl

    Run Linpack:
    ./xhpl

    Reply

  25. Regarding the performance decrease after the overclocking. I did some tests and found out that an unstable overclock can cause the CPU to slow itself down (not thermal throttling) and will require a reboot. For example, when I overclocked to 1350/over_voltage=4, and ran the

    “fulload() { dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null | dd if=/dev/zero of=/dev/null & }; fulload”

    everything seemed to be fine. The highest temperature was 56c. Then I ran the above mentioned command AND Quake3 at the same time. At first, I noticed a dramatic increase of the CPU temperature (up to 65c) and the PI’s power consumption was ~7.5W at peak. After a couple of minutes I noticed that things got slower – the CPU temperature suddenly dropped to 55c and power consumption dropped to ~5.5W so I figured that something was wrong. I added some more juice with over_voltage=6 and it now seem to be totally stable with no performance drops.

    The moral of this story: a thorough stability/performance testing is required or otherwise you may end up with a slower/unstable Pi.

    Reply

  26. Really fantastic article and very helpful. I’m having an issue with the temperate shell script.

    I wrote it out just as you have and placed is under ~/ — however, when I attempt to execute it (sudo watch ./check_cpu_speed_temp) I receive an error “Permission Denied”. Any idea what that could be from?

    If I just run sudo /opt/vc/bin/vcgencmd measure_temp it works fine and shows ~ 48.3C @ arm_freq=1000 and if I run the arm_freq command I get back 1000. So, those seem to be working but the cat automation is no good.

    Reply

      • I figured that out after I posted. Feeling like a fool now 🙂

        Now I’m trying to figure out how to get an AOC Usb monitor (16″) to work on this thing without having to repack and compile the Linux kernel. I don’t think it is possible. Any recommendations for a good monitor (doesn’t have ot be touch) that doesn’t have crap hanging out of it like everything on the market now? 10-13″ would be perfect.

        Reply

  27. Any idea why I get a permissions denied when running the watch ./check_cpu_speed_temp.sh command? I created it with the user I am logged in as so I have no idea why it would not allow.

    Reply

  28. Howdy – Yall!

    I wanted to jump in and say I overclocked my RPi3 almost as soon as i got it. It runs great. I moved it to Raspian Pixel and found I had to look for a little help and you guys all seem to have no issues with the specs which are very close to mine. I changed it a little after reading your posts. I got lucky with this one. Im not sure about the one over there still in a package. But this one can take a load. I keep it at 1325, 500, 500, 5 or 6 vol. and it seems to perform excellent with this mixture of specs. And, temps stay well within an excellent range. Not over 62C under heavy loads. I think thats great.

    Anyhow thanks for the information.

    Reply

  29. so i got my pi back in march and started running into power issues because my 5V2A just won’t cut it, i played around with using more than one of the 3 ways to power a pi3 and using an extra amp through the usb backpower (probably just .5amps getting through) it runs better but i still can’t get my pi to run at full 4-core 100% load without it using more power than is available. i wonder if my board was one of the “really bad” boards. although a sad 200MHz underclock allows me to use the cpu at 4-cores 100% load. i just run 3 really heavy dual threaded python programs that i built and see if the pi crashes/turns off. if not than i am good

    Reply

  30. Im gonna try the same as you, but step it up another notch. i imagine that watercooling is much more compact in terms of space, additionally to being relatively easy to make. as of right now i don’t even have the pi3 but i do have the pi1. there are very small watercooling blocks from alphacool such as the MCX one. how ever i would need to order it. it would be a fun project and i do want to see if i could do the same thing but with a pi zero.

    i would then use a hardcase to contain it etc.

    Reply

  31. Great article, thanks! I am looking to increase processing speed to see if I can improve my BOINC performance. Here’s what I did:

    arm_freq=1380
    core_freq=500
    over_voltage=4
    disable_splash=1
    force_turbo=1
    boot_delay=1
    sdram_freq=500

    It runs fine with just BOINC, but anytime I try to fire up another application (such as Chromium) the system freezes. Also, the visual CPU monitor rarely goes above 50%. Before this experiment, it typically ran at 100% (with BOINC running full throttle).

    Interested to see if this bumps up my numbers/performance.

    Reply

  32. hi
    i just want to supply power for other devices which uses 5v dc from the raspberry pi by cutting and soldering the wires and also i want to connect all the usb ports with mouse keybord wifi dongle and also i would like to connect my camera module to raspberry pi

    here my doubt is the is too much load on raspberry pi will that effect my pi

    Reply

  33. Hello, i first want to say thank you for taking the time to write your article because I found it very helpful in learning about overclocking!

    Second, I was wondering if you could tell me why I would not be able to execute the

    watch ./check_cpu_speed_temp.sh

    program that you advised writing? I am getting sh: 1: ./check_cpu_speed_temp.sh: Permission denied

    I have created it, and even went back in to it with sudo nano to make sure that it is created but I cannot get the watch command to activate it. Any recommendations please?

    Thank you.

    Reply

  35. Hello, my Pi is unstable at 1400 even with overvolt=6, so I decided to push SDRAM harder,
    these work stable for me:
    dtparam=sd_overclock=80
    arm_freq=1350
    core_freq=500
    gpu_freq=500
    over_voltage=4
    sdram_freq=600
    sdram_schmoo=0x02000020
    over_voltage_sdram_p=4
    over_voltage_sdram_i=2
    over_voltage_sdram_c=2
    gpu_mem=80
    I wonder whether running arm at 1200 while SDRAM is 1/2 of this would produce better results or async is not a problem. I did not notice so much speedup as result of this overclock except for sd card speed.

    Reply

    • Hmmm… I can get mine to 1400 and the settings I would up with run very nice – SDRAM has always been my struggle. I have mine set to (all else is default):

      arm_freq=1400
      gpu_freq=450
      over_voltage=4
      gpu_mem=256

      I’ve tried manipulating SDRAM several times, all doing subtle adjustments each time – it’ll boot, but it just gets the desktop background up…(?)

      Reply

  36. Hi, when I edit config.txt and reboot i haven’t any effects, freq can.t changed … its still 1200. When opened first time file, freq was changed by 800 but freq in device was 1200. RPi 3 B china clone

    Reply

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