6

I've just setup a raspberry pi 3 and found out that, on idle, the temperature is about 48 C (measured with vcgencmd measure_temp). On a raspberry pi B+ with the same enclosure and in the same environment I measured 37 C. Is this normal? The ambient temperature is about 22.5 C. Thanks

Case: https://www.amazon.com/dp/B00UW2G1BS

Power supply (for both): https://www.amazon.com/dp/B00VH8ZW02

  • 1
    About the same ambient temperature in a case with maybe a bit more ventilation, connected via wifi at idle I get 43 C; just did a system update and toward the end (while the processor is working modestly, and after some vigorous wifi activity), ~48 C. I wouldn't expect them to all be identical in this respect however, and yours does not sound out of line. I think the usual "operating temperature" stated by Broadcom for Pi SoCs is 45 C. The one in the 3 does seem to run a bit hotter than the others. It also sucks more energy so that is not surprising. – goldilocks Oct 21 '16 at 16:44
  • 1
    It looks like the case they shipped to me had the cut for the cpu suitable for the rpi 2 and B+, so it's a bit misplaced mounted on the rpi 3, covering part of the cpu itself. I tried removing the case at all and I get ~43 C as well. – Matteo Oct 21 '16 at 16:53
  • To be fair to case makers/retailers, the 2 and 3 (and B+) are almost identical form factor wise; the only significant difference is that on the 3 the wifi is where the ACT/PWR leds are on the 2 and B+ (which can make a difference with some cases in terms of visibility). The top cutout on that one is in the middle for aesthetics, I think -- none of them have the SoC there. Mine doesn't have one over the SoC either, but it does have a big hole over the pin breakout and then smaller ones over the CSI and DSI connectors. I can feel warmth rising up from the one over the CSI and GPIO ones. – goldilocks Oct 21 '16 at 17:04
  • ...A drill (and a round file for finishing) might be help. Also my case doesn't have that inner layer, and there's a big vent underneath the board (if you do drill, put a couple of holes there to create circulation). – goldilocks Oct 21 '16 at 17:04
  • 1
    Yeah, it's off by few millimeters only, however I think that inner layer played a major role against air flow. Definitely better without the case. – Matteo Oct 21 '16 at 17:25
8

I have eight pi3s in a room which is 22-24°C. They range in temperature between ~45°C and ~50°C when idle, with each pi being fairly consistent in temperature +-2°C (sorry, not terribly accurate values, they are from squinting at a plot). Mine aren't in any kind of enclosure, but are mounted on the underside of a plate with reasonably free air flow.
So your reading of 48°C is within what I see for the pi 3.
There's some info on power usage between the models here: Raspberry Pi 3 vs Pi 2 power consumption and heat dissipation
Your case looks to allow for a heat sink on the processor, no idea if it would make a difference if the limiting factor is heat leaving the case?

  • 1
    Also, it seems that wifi is playing a role (not unexpected). I tried using eth0 instead of wlan0 and i get ~45 C. – Matteo Oct 21 '16 at 15:56
  • Ah, mine have had an ssh connection via the ethernet as well. – Craig Oct 21 '16 at 16:08
5

I have a RPI3 with a mini heatsink, like the following image:

RPI

Both heat sinks (14x14x11 mm and 9x9x12 mm) are made of aluminium and the fan is a SEPA MF15B-05 (15x15x5mm, 5V-0.06A) that is soldered to the printed circuit board (so it is permanent :P)

So the iddle temperature with Raspbian Lite, WIFI connection and SSH active connection is about ~37°C in a 25°C environment (measured with 2 different DHT11), as the image:

Temp

Here are the results for sysbench (The temp (vcgencmd measure_temp) commands were executed immediately after sysbench):

pi@raspberrypi:~ $ temp
19/02/2017 01:34 temp=38.1'C
pi@raspberrypi:~ $ sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=20000 run
sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.

Doing CPU performance benchmark. 
Threads started!
Done.

Maximum prime number checked in CPU test: 20000

Test execution summary:
    total time:                          120.2905s
    total number of events:              10000
    total time taken by event execution: 481.0520
    per-request statistics:
         min:                                 47.69ms
         avg:                                 48.11ms
         max:                                107.84ms
         approx.  95 percentile:              48.15ms

Threads fairness:
    events (avg/stddev):           2500.0000/4.30
    execution time (avg/stddev):   120.2630/0.01

pi@raspberrypi:~ $ temp
19/02/2017 01:37 temp=41.3'C
pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=20000 run
sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.

Doing CPU performance benchmark
Threads started!
Done.

Maximum prime number checked in CPU test: 20000

Test execution summary:
    total time:                          120.2604s
    total number of events:              10000
    total time taken by event execution: 480.9000
    per-request statistics:
         min:                                 47.69ms
         avg:                                 48.09ms
         max:                                 79.81ms
         approx.  95 percentile:              48.19ms

Threads fairness:
    events (avg/stddev):           2500.0000/4.64
    execution time (avg/stddev):   120.2250/0.02

pi@raspberrypi:~ $ temp
19/02/2017 01:40 temp=51.5'C
pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=50000 run
sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.

Doing CPU performance benchmark

Threads started!
WARNING: Operation time (18446744073295001600.000000) is greater than maximal counted value, counting as 10000000000000.000000
WARNING: Percentile statistics will be inaccurate
Done.

Maximum prime number checked in CPU test: 50000

Test execution summary:
    total time:                          431.3375s
    total number of events:              10000
    total time taken by event execution: 1725.1204
    per-request statistics:
         min:                                171.26ms
         avg:                                172.51ms
         max:                            18446744073297.48ms
         approx.  95 percentile:             182.42ms

Threads fairness:
    events (avg/stddev):           2500.0000/4.64
    execution time (avg/stddev):   431.2801/0.06

pi@raspberrypi:~ $ temp
19/02/2017 01:47 temp=52.1'C
pi@raspberrypi:~ $ temp
19/02/2017 01:50 temp=38.6'C

pi@raspberrypi:~ $ temp
19/02/2017 01:58 temp=37.6'C
pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=threads --thread-yields=4000 --thread-locks=6 run
sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.

Doing thread subsystem performance test
Thread yields per test: 4000 Locks used: 6
Threads started!
Done.

Test execution summary:
    total time:                          11.8955s
    total number of events:              10000
    total time taken by event execution: 47.5581
    per-request statistics:
         min:                                  4.58ms
         avg:                                  4.76ms
         max:                                 38.03ms
         approx.  95 percentile:               4.78ms

Threads fairness:
    events (avg/stddev):           2500.0000/7.87
    execution time (avg/stddev):   11.8895/0.00

pi@raspberrypi:~ $ temp
19/02/2017 01:59 temp=41.9'C
pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=threads --thread-yields=40000 --thread-locks=6 run
sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.

Doing thread subsystem performance test
Thread yields per test: 40000 Locks used: 6
Threads started!
Done.

Test execution summary:
    total time:                          118.2965s
    total number of events:              10000
    total time taken by event execution: 473.0799
    per-request statistics:
         min:                                 45.83ms
         avg:                                 47.31ms
         max:                                289.45ms
         approx.  95 percentile:              47.96ms

Threads fairness:
    events (avg/stddev):           2500.0000/3.24
    execution time (avg/stddev):   118.2700/0.01

pi@raspberrypi:~ $ temp
19/02/2017 02:01 temp=52.6'C
pi@raspberrypi:~ $ temp
19/02/2017 02:01 temp=45.1'C
pi@raspberrypi:~ $ temp
19/02/2017 02:02 temp=41.3'C
pi@raspberrypi:~ $ temp
19/02/2017 02:02 temp=40.8'C
pi@raspberrypi:~ $ temp
19/02/2017 02:03 temp=39.7'C

If I remove the fan and the heatsink, the normal temperature is between 45°C and 47°C, with the same clean Raspbian lite installation (default background processes) and a environment temperature of 25°C in a room with quiet air flow.

pi@raspberrypi:~ $ temp
19-02-2017 16:30:56.962 temp=44.5'C
19-02-2017 16:31:19.031 temp=44.5'C
19-02-2017 16:46:13.289 temp=47.2'C
19-02-2017 16:47:22.807 temp=46.2'C
19-02-2017 16:30:56.962 temp=44.5'C
19-02-2017 16:31:19.031 temp=44.5'C
19-02-2017 16:46:13.289 temp=47.2'C
19-02-2017 16:47:22.807 temp=46.2'C

pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=20000 run &
[1] 6315
sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.

Doing CPU performance benchmark

Threads started!
pi@raspberrypi:~ $ temp
19-02-2017 16:49:34.027 temp=62.3'C
19-02-2017 16:49:39.227 temp=65.0'C
19-02-2017 16:49:51.345 temp=68.2'C
19-02-2017 16:50:05.845 temp=70.9'C
19-02-2017 16:50:16.557 temp=72.0'C
19-02-2017 16:50:29.352 temp=74.1'C
19-02-2017 16:50:44.018 temp=75.2'C
19-02-2017 16:51:01.537 temp=76.3'C
19-02-2017 16:51:12.767 temp=77.4'C

Done.
Maximum prime number checked in CPU test: 20000

Test execution summary:
    total time:                          120.3647s
    total number of events:              10000
    total time taken by event execution: 481.3170
    per-request statistics:
         min:                                 47.69ms
         avg:                                 48.13ms
         max:                                107.91ms
         approx.  95 percentile:              48.45ms

Threads fairness:
    events (avg/stddev):           2500.0000/5.61
    execution time (avg/stddev):   120.3292/0.02

19-02-2017 16:51:25.627 temp=70.9'C
[1]+  Hecho                   sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=20000 run
pi@raspberrypi:~ $ temp
19-02-2017 16:51:33.184 temp=63.4'C
19-02-2017 16:51:43.481 temp=59.1'C
19-02-2017 16:51:51.171 temp=58.0'C
19-02-2017 16:51:58.799 temp=56.9'C
19-02-2017 16:52:13.516 temp=54.8'C
19-02-2017 16:52:37.527 temp=53.7'C
pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=20000 run &
[1] 9002
pi@raspberrypi:~ $ sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.
Doing CPU performance benchmark
Threads started!

pi@raspberrypi:~ $ temp
19-02-2017 16:52:44.986 temp=59.6'C
19-02-2017 16:52:50.375 temp=66.1'C
19-02-2017 16:52:57.017 temp=69.8'C
19-02-2017 16:53:08.557 temp=73.1'C
19-02-2017 16:53:17.467 temp=75.2'C
19-02-2017 16:53:28.827 temp=75.2'C
19-02-2017 16:53:42.841 temp=77.4'C
19-02-2017 16:54:03.827 temp=79.5'C
19-02-2017 16:54:09.247 temp=79.5'C
19-02-2017 16:54:15.461 temp=79.0'C
19-02-2017 16:54:25.284 temp=80.1'C
19-02-2017 16:54:33.565 temp=80.1'C
pi@raspberrypi:~ $ Done.

Maximum prime number checked in CPU test: 20000
Test execution summary:
    total time:                          120.7209s
    total number of events:              10000
    total time taken by event execution: 482.8149
    per-request statistics:
         min:                                 47.69ms
         avg:                                 48.28ms
         max:                                 74.52ms
         approx.  95 percentile:              49.77ms

Threads fairness:
    events (avg/stddev):           2500.0000/5.52
    execution time (avg/stddev):   120.7037/0.01

pi@raspberrypi:~ $ temp
19-02-2017 16:54:45.399 temp=76.3'C
[1]+  Hecho                   sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=20000 run
19-02-2017 16:54:47.936 temp=72.0'C
19-02-2017 16:54:48.756 temp=71.4'C
19-02-2017 16:54:49.725 temp=69.8'C
19-02-2017 16:54:50.609 temp=68.8'C
19-02-2017 16:54:51.662 temp=68.2'C
19-02-2017 16:54:54.030 temp=65.5'C
19-02-2017 16:54:59.340 temp=63.4'C
19-02-2017 16:55:04.280 temp=62.3'C
19-02-2017 16:55:08.219 temp=61.2'C
19-02-2017 16:55:11.744 temp=60.1'C
19-02-2017 16:55:15.914 temp=59.1'C
19-02-2017 16:55:19.300 temp=59.1'C
19-02-2017 16:55:23.306 temp=58.0'C
19-02-2017 16:55:27.411 temp=57.5'C
19-02-2017 16:55:33.266 temp=56.9'C
19-02-2017 16:56:15.095 temp=55.3'C
19-02-2017 16:57:03.016 temp=52.1'C
pi@raspberrypi:~ $ sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=50000 run &
[1] 12616
pi@raspberrypi:~ $ sysbench 0.4.12:  multi-threaded system evaluation benchmark

Running the test with following options:
Number of threads: 4
Additional request validation enabled.
Doing CPU performance benchmark
Threads started!

pi@raspberrypi:~ $ temp
19-02-2017 16:57:22.717 temp=67.1'C
19-02-2017 16:57:25.064 temp=68.8'C
19-02-2017 16:57:46.095 temp=74.7'C
19-02-2017 16:57:55.097 temp=75.2'C
19-02-2017 16:58:06.956 temp=76.8'C
19-02-2017 16:58:13.016 temp=77.4'C
19-02-2017 16:58:25.937 temp=78.4'C
19-02-2017 16:58:35.897 temp=79.5'C
19-02-2017 16:58:51.417 temp=80.6'C
19-02-2017 16:59:32.226 temp=81.7'C
19-02-2017 16:59:49.787 temp=80.6'C
19-02-2017 17:00:31.352 temp=81.1'C
19-02-2017 17:00:42.532 temp=81.7'C
19-02-2017 17:02:46.227 temp=81.7'C
19-02-2017 17:03:22.253 temp=82.2'C
19-02-2017 17:04:37.505 temp=81.7'C
pi@raspberrypi:~ $ Done.

Maximum prime number checked in CPU test: 50000

Test execution summary:
    total time:                          500.6550s
    total number of events:              10000
    total time taken by event execution: 2002.3821
    per-request statistics:
         min:                                171.32ms
         avg:                                200.24ms
         max:                                460.88ms
         approx.  95 percentile:             224.74ms

Threads fairness:
    events (avg/stddev):           2500.0000/6.00
    execution time (avg/stddev):   500.5955/0.06

[1]+  Hecho                   sudo sysbench --num-threads=4 --validate=on --test=cpu --cpu-max-prime=50000 run

pi@raspberrypi:~ $ temp
19-02-2017 17:05:45.548 temp=67.7'C
19-02-2017 17:05:51.425 temp=65.5'C
19-02-2017 17:06:28.859 temp=60.1'C
19-02-2017 17:06:51.751 temp=58.0'C
19-02-2017 17:07:02.178 temp=57.5'C
19-02-2017 17:07:39.439 temp=54.8'C
19-02-2017 17:07:56.307 temp=54.8'C
19-02-2017 17:08:17.866 temp=54.8'C
19-02-2017 17:08:32.100 temp=53.7'C
19-02-2017 17:09:17.898 temp=52.1'C
19-02-2017 17:10:02.736 temp=51.0'C
19-02-2017 17:10:40.158 temp=51.5'C
19-02-2017 17:14:35.286 temp=49.4'C
  • 1
    I'm not sure this really answers the question given that the OP was asking for the normal temperature of the Pi 3. Your results are for a Pi with active cooling, which is going to produce different results. If you added results for your Pi without cooling and what the ambient temperature was, you could make a really good comparison between an actively and passively cooled Pi. – Darth Vader Feb 19 '17 at 9:53
  • @DarthVader Done, I added some data to make a comparison – UselesssCat Feb 19 '17 at 20:36
  • I still have a question, the maximum temperature at which my raspberry arrived is 80 ° C. I wonder if this can be configured: P more than 85°C – UselesssCat Feb 19 '17 at 21:07
  • 1
    Max temp is 85°C, anything above this and the Pi will thermal throttle to bring the temperature back down. Running at anything higher than that risks damaging the SoC. – Darth Vader Feb 20 '17 at 8:52

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