I mean honestly what do you expect using an 8 core CPU and a beefy GPU? You expect things to be silent? This is an iMac with 1 fan. I don’t think you will find an Apple AIO computer that will ever be silent.
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Cooling in the new 2020 27" iMac?
- Thread starter miretogo
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I mean honestly what do you expect using an 8 core CPU and a beefy GPU? You expect things to be silent? This is an iMac with 1 fan. I don’t think you will find an Apple AIO computer that will ever be silent.
The first thing I do with any hyperthreading mac is permanently disable hyperthreading. If you look at geekbench scores (for what they're worth) hyperthreading makes about a 3% difference in speed, and turning it off helps the processor run a bit cooler.
Then, when the situation calls for it, I also disable turbo boost. With turbo boost off any iMac will run completely cool.
How to disable hyper-threading on your Mac
1. Turn on and restart your Mac then immediately press the Command+R or another macOS Recovery key on your keyboard.
2. Choose Terminal from the Utilities menu from the menu bar.
3. Type the following command into the Terminal prompt: nvram boot-args="cwae=2"
4. Press return then type: nvram SMTDisable=%01
5. From the Apple menu, press Restart.
I think even the Radeon Pro 5700XT is better than the Vega 56 in the stock iMac Pro.
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I personally wouldn't buy a 4000$ machine to cripple it by disabling hardware features.
If you want to spend that kind of money for 3 year old tech and then no do anything with it because your too scared of the fan then I don’t know what else to say.
Why would I not do anything with it? All reviews I read and watched mention, that the fans only spin up under extreme loads and that it's basically not noticeable for all the other cases.
Let's have fun.
iMac Pro doesn't have user upgradable RAM.
So if you want a higher specced iMac Pro than the iMac, you need :
- Upgrade to at least 64 GB of RAM (+500$CAD). I don't even consider 128 GB upgrade because one must be freaking crazy to pay +2500$ CAD for this upgrade.
- Upgrade to a 14 core CPU (because iMac Pro, you need to be a step above iMac because) (+1000$ CAD)
Considering you don't want a lower performing GPU, you upgrade to Vega 64X for a whopping 8709$ iMac Pro.
Ok, ok. 14 cores might be too much. Keep the 10 core which is less performant than the 10 core in the iMac 2020 (considering you are crazy enough and want a lower performing chip than the consumer grade one)
Finally a 7709 $ "budget" iMac Pro.
The price of silence hen ?
As I mentioned in the other thread, the difference for me is around 1500€.
3700€ for the imac pro (10 core, 64gb, vega64x) and 2200€ for the imac 2020 (i7, 64gb, 5700xt, 10gb lan).
iMac Pro has superior heat management, ECC ram and better audio..
What I need most is a reliable mac machine which is quite and runs all the software I am using. I am not sure if the software I am using will be optimized for AS right away. So, that is a question mark as well.
Whats wrong with buying an iMac Pro to bridge the time until 2nd gen macs with AS?
Because your paying ALOT more money for worse performance comparatively and your sole focus is the fan noise. You act like the fan on the 5k iMac is a jet engine or something. It’s just a foolish investment what your contemplating doing.
The fan ramped up to 2500RPM everytime I (just) started Photoshop. You cant tell me that this is fine...
No that probably isn’t fine so you just immediately return it? Why not see if something else is causing that.Maybe it was a faulty unit? Maybe you were running something in the background? It honestly should not do that. I have mine sitting right in front of me and it never leaves idle honestly for almost anything. The only time I’ve really got the fans going was when I slammed the CPU 100%. Otherwise this thing is dead silent.
I used the machine for around a week before returning it.
On idle I had 1400RPM at 60-70°C. Room temp around 24°C.
Event just opening PowerPoint or similar Apps would cause an increase to 2000RPM while the CPU runs up to 90°C and higher...
Using zoom with screen share: constant ~2200RPM.
....
I assumed these numbers are normal since I read many times in this forum that the 2020 iMac will not be as silent as an older one, but in the end the fan speed was too annoying to me...
Go buy the iMac pro. I think that's the best bet for you. Apple loves customers like you that will spend ridiculous amounts of money for no purpose lol.
60-70°C? I do not think that this was on idle. It should be 10 to 20 °C lower.
Maybe Spotlight was indexing or some other processes or apps in the background?
Have you checked activity monitor?
This is true. As far as the inefficient but powerful Intel and the 'last year mid range' AMD gpu.
It is a lot of power in an A.i.O case that has not changed. A lot of performance unprecedented in an iMac. You can tell the motivation that prompted Apple to go AS.
And there's the rub.
Apple could have put better cooling in this. They didn't.
It's a fine last Intel iMac. But it is the end of the road.
It's a shame this didn't get a process shrink Intel CPU and an AMD RDNA2.
But then, that would be a higher bar for AS to beat...
Azrael.
The first thing I do with any hyperthreading mac is permanently disable hyperthreading. If you look at geekbench scores (for what they're worth) hyperthreading makes about a 3% difference in speed, and turning it off helps the processor run a bit cooler.
Then, when the situation calls for it, I also disable turbo boost. With turbo boost off any iMac will run completely cool.
How to disable hyper-threading on your Mac
1. Turn on and restart your Mac then immediately press the Command+R or another macOS Recovery key on your keyboard.
2. Choose Terminal from the Utilities menu from the menu bar.
3. Type the following command into the Terminal prompt: nvram boot-args="cwae=2"
4. Press return then type: nvram SMTDisable=%01
5. From the Apple menu, press Restart.
That's an interesting and creative response to the cooling debate.
What's been intriguing is the way that the fans kick in even when opening the user interface of Z-Brush. I didn't realise an App could make a Mac work so hard.
. Something that didn't even stress my 2012 iMac.Maybe it would it would be an interesting idea if Apple would allow the turbo function to be turned off for a more measured cooler running iMac. Or have different performance modes depending on burst tasks or more measured computing tasks.
The turbo feature seems to (yes) get the performance going...but it also gets the 'heat' going in burst modes...and the fans (I mean 'fan') have to kick in.
I wonder how this turbo yo-yoing effects the life span of components. 0-60mph then slamming the breaks on. As to a more measured response to a performance task.
Coupled with the irony of turning off the turbo on pricey kit like the iMac.
Still. An interesting response. Even at stock clock without the turbo burst, the Intel CPU should handle rendering in its sleep. It is spread out over ten cores.
I guess the other thing is...is the turbo just on 1 core, 2 cores...or all cores that is causing this 'flush' of heat. (Added to the fact that the fans are 'so...very...' slightly audible even when the iMac is sat in idle doing 'nothing.'). Maybe having 10 cores at 'stock' 3.6 clocks rather than pegging at 4 gig + could be an option. (Yes. I can hear the bells of irony deafening me as I type.)
And just offering decent cooling to keep pace with the internals wouldn't have gone amiss.
Azrael.
I haven't checked the used iMac Pro prices since the iMac 2020 was released.
Azrael.
The fans have kicked in 'just' for opening Z-Brush and opening up the Light Box interface...and pulsed out again.
In general I find this machine is quiet unless you push it. (3D renders.). That is generally true.
But I don't class opening an app and looking through the interface as 'pushing it.'
Azrael.
Another 'offending' app. Is Blender. I've merely 'opened' that app. And the fans pulsed in. Then out.
I've opened Z-Brush. Lightwave 3D (that didn't cause the fans to pulse.). Poser 11. Blender.
The two apps that cause a 'pulse' of fans are Z-Brush and Blender. Then the fans go quiet again.
Not doing anything. Just being 'open.' Rotating the view in Blender? Causes the fans to pulse in. And out.
The model? A simple cube.
Azrael.
I've opened Z-Brush. Lightwave 3D (that didn't cause the fans to pulse.). Poser 11. Blender.
The two apps that cause a 'pulse' of fans are Z-Brush and Blender. Then the fans go quiet again.
Not doing anything. Just being 'open.' Rotating the view in Blender? Causes the fans to pulse in. And out.
The model? A simple cube.
Azrael.
Well. If you bought used with a warranty. You could save some money and have the cooling you're after.
Also consider. The iMac Pro may yet...(!) get an update before long with the RDNA2 gpu (a MAC part has been listed...)
The RDNA2 is not far away. 28th of October? So if you're thinking of going 2020 and want the iMac Pro as a comparison.
ie to pay the extra for the cooling (proper cooling to go with performance parts...)
Azrael.
iMac temps currently 40C while surfing here and watching YouTube clips.
Haven't run into fans speeding up while igniting Blender, but it's possible generating the default cube takes more power than you think.
(Internal CPU image of Blender default cube being generated at program open.)
Haven't run into fans speeding up while igniting Blender, but it's possible generating the default cube takes more power than you think.
(Internal CPU image of Blender default cube being generated at program open.)