On Mon, Apr 2, 2018 at 12:36 PM, Adam Holt <h...@laptop.org> wrote: > On Mon, Apr 2, 2018 at 10:44 AM, Adam Holt <h...@laptop.org> wrote: > >> 1) Recap from 2016: heatsinks on the original RPi3 CPU are not a cure-all >> when the RPi 3 is enclosed in a case that lacks ventilation on a hot day. >> But CPU heatsinks Do Work when taking the plastic top off the of the >> original RPi 3. The CPU throttling problem "immediately" goes away on such >> hot days...bringing the temperature back down below 80C...as measured by >> the command: >> >> *vcgencmd measure_temp* >> >> 2) It's snowing today right outside my window, so I can't easily simulate >> a hot summer's day -- but can others who live in hot environments report >> back their readings above, when running the new RPi3 B+ in various >> conditions? >> >> - *With heatsink on CPU -- and without?* >> - *With motherboard fully enclose by a case -- and without?* >> >> > My own results, with all 4 CPU's unloaded, in a chilly room: >
RPi 3 with-heatsink-on-CPU / RPi 3 B+ / RPi 3 B+ with-heatsink-on-CPU 44-46C / 46-48C / 45-47C case's plastic top removed (w/o wind or active ventilation) 46-49C / 48-51C / 48-52C case's plastic top attached (contains 100+ small holes on 1 end, allowing very little ventilation) After I ran "*yes > /dev/null &*" 4 times, to fully load all 4 cores of the > CPU: > RPi 3 with-heatsink-on-CPU / RPi 3 B+ / RPi 3 B+ with-heatsink-on-CPU 80-82C / 70-71C / 71-72C case's plastic top removed (w/o wind or active ventilation) 82-84C / 75-78C / 79-82C case's plastic top attached (contains 100+ small holes on 1 end, allowing very little ventilation) *RESULT: attaching a heatsink to the RPi 3 B+ CPU does not help. It might even make things a bit worse, hmm.* In any case: this result is completely different the original RPi 3 (where past experiments have shown that a heatsink-on-CPU greatly lowers its temperature, When The Case Is Open!) > CONCLUSION: the RPi 3 B+ appears to be a real winner in CPU-intensive > conditions, even in a "wintry" conditions (room is about 15C, and it > continues to snow right outside the window). The RPi 3 CPU is supposed to > self-throttle at 80C, until it just about turns itself off at 85C. I'd > assume the RPi 3 B+ CPU does the same? But do not know for sure. Thanks > to all who can add any similar data points, in warmer climate/conditions. > > > CLARIFS: Both RPi's were running a near-final prerelease of > Internet-in-a-Box 6.5 on Raspbian Lite to explore real-world conditions. > I waited 10+ min in all above 8 experiments before taking "steady state" > temp readings. Still, fluctuations in CPU activity (and temperature) > arise, even long after I ran "killall yes" to end the most intensive CPU > activity. > > > 3) Prelim thermal analysis of RPi 3 B+: >> >> https://cdn-images-1.medium.com/max/1600/1*0jU89Yu_6miI-CODBMuHAw.png >> https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi >> -3-b-plus-44122cf3d806 >> >> -- >> >> <https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi-3-b-plus-44122cf3d806> >> >> <https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi-3-b-plus-44122cf3d806> >> Unsung Heroes of OLPC, interviewed live @ >> <https://medium.com/@ghalfacree/benchmarking-the-raspberry-pi-3-b-plus-44122cf3d806> >> http://unleashkids.org ! >> >> -- >> Unsung Heroes of OLPC, interviewed live @ http://unleashkids.org ! >> >
_______________________________________________ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel