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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

Matteo
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    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
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    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
  • "covering part of the cpu" -> Maybe that inner layer is sitting a bit wrong? Counting on the GPIOs, I'd say the SoC on the 2 and 3 are in exactly the same spot in the long dimension but maybe on the 2 is a millimeter or so closer to the center line. – goldilocks Oct 21 '16 at 17:12
  • Hmm -- here's another factor I hadn't considered. I took a ribbon cable off the 3 so I could count the SoC position and noticed all the pins are actually warm to the touch, so they are diffusing heat out from the core, which the ribbon cable probably helped with. Checking the temp with the ribbon cable off it's now 46 C. – goldilocks Oct 21 '16 at 17:25
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    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

2 Answers2

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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?

Community
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Craig
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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
UselesssCat
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    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 09:53
  • @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
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    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 08:52