iMac Pro 10.13.4 Update Changed The iMac Pro's Fan Behavior

How Would You Prefer Your iMac Pro's Fans To Function?


  • Total voters
    25
  • Poll closed .

ThatSandWyrm

macrumors regular
Original poster
Oct 30, 2017
249
211
Indianapolis
Updated to MacOS 10.13.4 last night, and I'm noticing quite a difference in the way the internal fan is working.

Before, you'd never hear it at all until it kicked in under a HEAVY load, then it would run at maximum until it reached some preset temp, and would suddenly fade out.

Now, the fan speed ramps up and down slowly, much like a regular iMac does, through multiple speeds. From quiet whisper, to full on hair dryer, and everything in between.

Performance, especially for GPU computations seems nicely improved (less throttling?). But I'd really like some method of telling it whether to "run silent", or "run fast" while I'm working.
 
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chscag

macrumors 68040
Feb 17, 2008
3,740
1,293
Fort Worth, Texas
Before 10.13.4 I could hear the fan running in my 2017 5K iMac even when it was at around 1200 RPM (normal); now I can hardly hear it all at the same RPM. I wonder if Apple included a small firmware update with 10.13.4?
 

ThatSandWyrm

macrumors regular
Original poster
Oct 30, 2017
249
211
Indianapolis
Before 10.13.4 I could hear the fan running in my 2017 5K iMac even when it was at around 1200 RPM (normal); now I can hardly hear it all at the same RPM. I wonder if Apple included a small firmware update with 10.13.4?
They've updated the firmware in every iMP update this year. You can tell because of the double-reboots during the patch installation.
 
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sputnikBA

macrumors 6502
Jan 2, 2018
275
366
A setting was something I had hoped for tbh.

Normally most people could be content with letting the system auto-manage the cooling situation, but I'm willing to wager that the types of people willing to shell out the money for an iMac Pro would definitely benefit from an ability to prioritise cooling for performance or throttling for silent operation.

It doesn't even need to be deeply technical, just two options:

1) Prioritise quiet operation (set as default, as it is still providing excellent perf rates)
2) Prioritise performance (opt-in in settings)
 
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FredT2

macrumors 6502a
Mar 18, 2009
561
99
Updated to MacOS 10.13.4 last night, and I'm noticing quite a difference in the way the internal fan is working.

Before, you'd never hear it at all until it kicked in under a HEAVY load, then it would run at maximum until it reached some preset temp, and would suddenly fade out.

Now, the fan speed ramps up and down slowly, much like a regular iMac does, through multiple speeds. From quiet whisper, to full on hair dryer, and everything in between.

Performance, especially for GPU computations seems nicely improved (less throttling?). But I'd really like some method of telling it whether to "run silent", or "run fast" while I'm working.
I noted this in a post a week or two back. For my workloads I hear the ramping up and down, but not to anything approaching full on. The fans oscillate between about 1400 and 1650 rpm. 1650 is enough to be a bit bothersome. Temperature stays around 94 C.

I haven't noticed any real performance improvements, but then I haven't timed anything to really know. Handbrake doesn't really use the GPU,however.
[doublepost=1523224165][/doublepost]
Before 10.13.4 I could hear the fan running in my 2017 5K iMac even when it was at around 1200 RPM (normal); now I can hardly hear it all at the same RPM. I wonder if Apple included a small firmware update with 10.13.4?
Idle fan speed on my computer is 1100 rpm (at least that's what iStat reports). I could hear the fans on 10.13.3 and still hear them on 10.13.4, though admittedly it's very faint.
 

Redneck1089

macrumors 65816
Jan 18, 2004
1,164
273
I don't know about Fan behaviour, but now I am having trouble keeping my iMac Pro asleep; it keeps waking periodically and the temperatures are sitting around 45 degrees Celsius.

Also, once I reboot, my screen brightness is almost at maximum. The system remembers the brightness of my other screens, but not the iMac Pro's. 10.3.3 was far more reliable for me.
 
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ThatSandWyrm

macrumors regular
Original poster
Oct 30, 2017
249
211
Indianapolis
I don't know about Fan behaviour, but now I am having trouble keeping my iMac Pro asleep; it keeps waking periodically and the temperatures are sitting around 45 degrees Celsius.

Also, once I reboot, my screen brightness is almost at maximum. The system remembers the brightness of my other screens, but not the iMac Pro's. 10.3.3 was far more reliable for me.
I'm now seeing more app crashes, and extreme flickering on all screens when switching a 3D game from full-screen to windowed. Seems this one is half-baked.
 

FredT2

macrumors 6502a
Mar 18, 2009
561
99
I don't know about Fan behaviour, but now I am having trouble keeping my iMac Pro asleep; it keeps waking periodically and the temperatures are sitting around 45 degrees Celsius.

Also, once I reboot, my screen brightness is almost at maximum. The system remembers the brightness of my other screens, but not the iMac Pro's. 10.3.3 was far more reliable for me.
I'm not seeing any sleep problems, but screen brightness has been reported elsewhere. It seems to be a new feature.
 

anticipate

macrumors 6502a
Dec 22, 2013
535
290
I noticed that too last night. Though even at full blast it never seems extraordinarily loud. The two fans help. You can override this to some degree I believe with iStat Menus.
 

alkar

macrumors regular
Jan 12, 2008
165
22
Yeah noticed that too. I can hear them even in idle if I get close to it. It's minor, but I'm not sure it's less noisy than iMac 2013 I had before. Thought they were supposed to be more silent.

Although, they are now quite silent even on load. Definitely more than any iMac I've ever gotten.
 

SecuritySteve

macrumors 6502a
Jul 6, 2017
838
973
California
And... This morning I tried to wake my iMP from sleep and discovered that it had crashed. Something that previous updates had fixed. One step forward, two steps back.
I had this issue yesterday too. I've also noticed my CPU / GPU are at 140 degrees F when I wake from sleep, and my fans are not turning on during sleep to cool down my CPU / GPU. I don't know why it needs to heat up so much, and I'm disconnecting devices during sleep to try and identify if this is an external device issue or a OS level issue.
 

Redneck1089

macrumors 65816
Jan 18, 2004
1,164
273
I had this issue yesterday too. I've also noticed my CPU / GPU are at 140 degrees F when I wake from sleep, and my fans are not turning on during sleep to cool down my CPU / GPU. I don't know why it needs to heat up so much, and I'm disconnecting devices during sleep to try and identify if this is an external device issue or a OS level issue.
Please keep us posted on your findings. I’m experiencing the same.

This update has been garbage.
 

SecuritySteve

macrumors 6502a
Jul 6, 2017
838
973
California
Please keep us posted on your findings. I’m experiencing the same.

This update has been garbage.
At this point I've disconnected my Razer peripherals and my external drive, and still have the same heating issue. Tonight I will try again with everything disconnected at once. If that doesn't fix it, then it is a system level bug that Apple needs to fix.
 

Bryan Bowler

macrumors 68040
Sep 27, 2008
3,800
3,680
At this point I've disconnected my Razer peripherals and my external drive, and still have the same heating issue. Tonight I will try again with everything disconnected at once. If that doesn't fix it, then it is a system level bug that Apple needs to fix.
Steve, my iMac Pro started heating up big time when sleeping, and continues to do so even with nothing connected to it. One time, while sleeping, it was so hot that I thought I burned my hand when I touched it. Now I can't let it sleep and have to shut it down when I step away, but that is an entirely different issue in of itself due to SoftRAID no longer working properly with the iMac Pro and High Sierra. (There's a workaround for the SoftRAID issue, but it requires about 5 minutes of work every time I restart the computer.)

In the last 48 hours, I've become rapidly dissatisfied and am getting close to making this iMac Pro a $13K paperweight and setting it aside...and using another machine to get my work done.
 

SecuritySteve

macrumors 6502a
Jul 6, 2017
838
973
California
Steve, my iMac Pro started heating up big time when sleeping, and continues to do so even with nothing connected to it. One time, while sleeping, it was so hot that I thought I burned my hand when I touched it. Now I can't let it sleep and have to shut it down when I step away, but that is an entirely different issue in of itself due to SoftRAID no longer working properly with the iMac Pro and High Sierra. (There's a workaround for the SoftRAID issue, but it requires about 5 minutes of work every time I restart the computer.)

In the last 48 hours, I've become rapidly dissatisfied and am getting close to making this iMac Pro a $13K paperweight and setting it aside...and using another machine to get my work done.
Really!? That is crazy. I can't believe Apple QA would miss this, since it's such an obvious bug and major flaw! Who knows how many days of lifetime our machines are losing due to poor OS development.

This kind of thing makes me really worried about the future of Apple and the professional sector.
 

SRLMJ23

macrumors 68020
Jul 11, 2008
2,119
1,081
Central New York
Just curious who the one person is who voted for the "Always as silently as possible, even if performance is lowered!" option?! Who wants their performance lowered on ANY machine, let alone a $5,000+ machine? Very odd to me.

:apple:

 

FredT2

macrumors 6502a
Mar 18, 2009
561
99
At this point I've disconnected my Razer peripherals and my external drive, and still have the same heating issue. Tonight I will try again with everything disconnected at once. If that doesn't fix it, then it is a system level bug that Apple needs to fix.
Have you looked at power draw when sleeping? I just checked mine, and it starts out at 8 watts when first sleeping, dropping to 4. Temperature was 80 F coming out of sleep after about 30 minutes of sleeping. I'm on 10.13.4.
[doublepost=1523385067][/doublepost]
Steve, my iMac Pro started heating up big time when sleeping, and continues to do so even with nothing connected to it. One time, while sleeping, it was so hot that I thought I burned my hand when I touched it. Now I can't let it sleep and have to shut it down when I step away, but that is an entirely different issue in of itself due to SoftRAID no longer working properly with the iMac Pro and High Sierra. (There's a workaround for the SoftRAID issue, but it requires about 5 minutes of work every time I restart the computer.)

In the last 48 hours, I've become rapidly dissatisfied and am getting close to making this iMac Pro a $13K paperweight and setting it aside...and using another machine to get my work done.
What does Apple support say about this?
 

Bryan Bowler

macrumors 68040
Sep 27, 2008
3,800
3,680
Really!? That is crazy. I can't believe Apple QA would miss this, since it's such an obvious bug and major flaw! Who knows how many days of lifetime our machines are losing due to poor OS development.

This kind of thing makes me really worried about the future of Apple and the professional sector.
It is very worrisome to me too. The MacOS software quality assurance really needs to be fixed.

What does Apple support say about this?
I had already reset the NVRAM/PRAM before calling support. I called them this morning and had to endure resetting everything again and then as expected, they wanted me to do a complete fresh install of MacOS, which I had just done a little over a week ago. I told them no way since I had just done that and it takes me about 4-5 hours to do a fresh install (I have a lot of external software that I use for business.) As expected, they forwarded me to a senior advisor and she insisted that I do another fresh install before Apple would do anything and escalate the issue further.

I'm departing in 3 days for another 12-day filming segment for a project I'm working on and I cannot afford another day of downtime to do a second fresh OS install. So I ended the call and got back to work, even though it means I have to limp along with this problem for now.

When I get back in two weeks, if a fix is not out and I can't solve the problem with yet another fresh OS install, then I will contact my Apple Business rep and see what my options are.
 

sputnikBA

macrumors 6502
Jan 2, 2018
275
366
Just curious who the one person is who voted for the "Always as silently as possible, even if performance is lowered!" option?! Who wants their performance lowered on ANY machine, let alone a $5,000+ machine? Very odd to me.

:apple:
I can’t speak for that person specifically, but a balance between silence and performance is useful to people who work with audio. Me personally though, I’d rather see it as a setting like I suggested above.
 
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FredT2

macrumors 6502a
Mar 18, 2009
561
99
It is very worrisome to me too. The MacOS software quality assurance really needs to be fixed.



I had already reset the NVRAM/PRAM before calling support. I called them this morning and had to endure resetting everything again and then as expected, they wanted me to do a complete fresh install of MacOS, which I had just done a little over a week ago. I told them no way since I had just done that and it takes me about 4-5 hours to do a fresh install (I have a lot of external software that I use for business.) As expected, they forwarded me to a senior advisor and she insisted that I do another fresh install before Apple would do anything and escalate the issue further.

I'm departing in 3 days for another 12-day filming segment for a project I'm working on and I cannot afford another day of downtime to do a second fresh OS install. So I ended the call and got back to work, even though it means I have to limp along with this problem for now.

When I get back in two weeks, if a fix is not out and I can't solve the problem with yet another fresh OS install, then I will contact my Apple Business rep and see what my options are.
Sorry. That process can be so frustrating. They have their script and can't deviate from it no matter how much you've put into solving the problem before calling.

At this point it might be best just to put on 10.13.4 and see what it does.
 

Bryan Bowler

macrumors 68040
Sep 27, 2008
3,800
3,680
Sorry. That process can be so frustrating. They have their script and can't deviate from it no matter how much you've put into solving the problem before calling.

At this point it might be best just to put on 10.13.4 and see what it does.
I’m thinking you’re right. At this point, since I’m departing in a few days, I’ll take a wait and see approach and if nothing new is learned by the time I get back, then I’ll go ahead and move to 10.13.4 and see what happens.
 
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