iMac Runs Hot with SETI

Questions and Answers : Macintosh : iMac Runs Hot with SETI
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Message 1867149 - Posted: 13 May 2017, 18:39:42 UTC
Last modified: 13 May 2017, 18:56:30 UTC

I've been running BOINC projects for several years.
My iMac, late 2015 and running El Capitan, has 4 processors, so at any given time there are 4 different programs running from seven different projects.
Lately, the SETI programs have sent the temperature soaring on the iMAC from about 100° to 160° while it's in idle/sleep mode.
The fan kicks in around 125° but the temp keeps climbing until I wake up the mac.
No other programs, or any combination of them, are causing this problem. It happens even when running one SETI project at a time.
Because of this, I've suspended SETI from running at night .
At the moment, there are over 30 projects with a running time of 27:06 min in the queue with the parameters (0.00708 CPUs + 1 Intel GPU) waiting their turn. If I could run four of them at a time, without fear of ruining my computer, they would be processed in 8 hours instead of the days it takes now.

Is there anything I can do, or that you can do, to stop the overheating? Will the upcoming BOINC upgrade being Beta tested now stop the overheating. If so, I'll download it now.

And btw, I really do miss the SETI screensaver which no longer runs because all of my assigned projects require GPU.
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Message 1867228 - Posted: 14 May 2017, 6:43:18 UTC

The latest SETI applications are more demanding on the processors, thus one can expect higher operating temperatures. This is particularly true of the GPU applications.
One action you may consider is to ensure that the cooling system is clear of accumulated dust, dust can collect quietly and have no effect until a point where suddenly the cooling system is too heavily clogged up, and the temperature skyrockets. I realise this will mean opening up your Mac, and that may be fraught with difficulties due to the way some Macs have been assembled.
The version BOINC you use will have very, very, very little impact on the running temperature of the computer.
Bob Smith
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Message 1867438 - Posted: 15 May 2017, 15:12:19 UTC - in response to Message 1867149.  

I had the same problem on my Mac pro tower, with 4 processors. That's when I discovered that little thing has a big fan! So I just reduced the max % of CPU allowed in the parameters.
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Message 1881377 - Posted: 31 Jul 2017, 19:53:01 UTC
Last modified: 31 Jul 2017, 19:53:43 UTC

I have a similar problem with my MacBook Pro (Late 2016). As suggested by Arial&Jeff S, I've been dialing down the max % of CPU with no luck. It's now set at 5%. At this setting everything is fine till I walk away and come back 10-15 min later when the display is off. By this time Macs Fan Control reports both fans maxed out at 6336 & 6864 rpms and cpu temps just under 200F. Yikes!!! I've suspended BOINC for the time being.

I also have BOINC running on my Late 2015 iMac. It's configured at 10% max, and seems to be running just fine. I occasionally hear the fans speed up (not to max) then ramp down.

Any suggestions?


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Message 1882415 - Posted: 6 Aug 2017, 14:42:27 UTC - in response to Message 1881377.  

Update. It appears the GPU is at the root of excessive fan use. As I stated before, while using my MacBook Pro everything was fine but when in screen saver mode (blank screen) the fans would crank up. Issue resolved when I disabled use of the GPU (<no_gpus>). No or little fan action now.
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Message 1889381 - Posted: 12 Sep 2017, 4:52:40 UTC

I just take the screws out of the back of the MacBook aluminum case and remove the back cover. Now I use a laptop pad fan below on a un used work table. Now I get the most out of the GPUs without overheating it all night.
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Questions and Answers : Macintosh : iMac Runs Hot with SETI

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