You're right about the idling poise of the iMac. I've noticed it. Most of the time it's not really noticeable. Maybe I've got used to it.
Are you temps on this iMac more than the 2017? At idle? Doing workloads?
Thanks for the input.
Azrael.
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Cooling in the new 2020 27" iMac?
- Thread starter miretogo
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You're right about the idling poise of the iMac. I've noticed it. Most of the time it's not really noticeable. Maybe I've got used to it.
Are you temps on this iMac more than the 2017? At idle? Doing workloads?
Thanks for the input.
Azrael.
WoW. I've posted a reasonable amount on WoW. It's a game I used to play a lot of.
My old iMac could play it without a fan blowing. And. So can this iMac.
Tested on Quality WoW settings '10.' (WoW fans will know what these ratings are. In game performance to quality settings 1 to 10.)
If by 'low' you mean HD or QHD. No problems. If you mean 'low' on 4k or 5k you should have no problems.
HD. Rock solid max fps.
QHD. Rock solid max fps.
4k. Rock solid max fps.
5k. This is where you'll have to tweak a bit. I found on setting '5' I was getting around 93 fps. No fans. I was impressed. For quality setting 10? Fans. Loud. Hair dryer mode. So if you ran on settings 1-4 at 5k I dare say you could max at the FPS at 5k native.
I hope that helps.
If you want to play WoW. 2020 iMac will throw it around the bedroom. Np.
I would say. For the difference in the graphical fidelity you get you may as well play QHD. Sound visuals. Sound performance.
4k. Again. No problem in this mode. Try it.
5k. Again. Just balancing the perf vs quality visuals.
There's no much in it. But if you want to do perf/quality mix at '5' and have 93 fps at 5k then you can.
I'd be interested to hear if other iMac WoW players have similar benches in testing.
Azrael.
My old iMac could play it without a fan blowing. And. So can this iMac.
Tested on Quality WoW settings '10.' (WoW fans will know what these ratings are. In game performance to quality settings 1 to 10.)
If by 'low' you mean HD or QHD. No problems. If you mean 'low' on 4k or 5k you should have no problems.
HD. Rock solid max fps.
QHD. Rock solid max fps.
4k. Rock solid max fps.
5k. This is where you'll have to tweak a bit. I found on setting '5' I was getting around 93 fps. No fans. I was impressed. For quality setting 10? Fans. Loud. Hair dryer mode. So if you ran on settings 1-4 at 5k I dare say you could max at the FPS at 5k native.
I hope that helps.
If you want to play WoW. 2020 iMac will throw it around the bedroom. Np.
I would say. For the difference in the graphical fidelity you get you may as well play QHD. Sound visuals. Sound performance.
4k. Again. No problem in this mode. Try it.
5k. Again. Just balancing the perf vs quality visuals.
There's no much in it. But if you want to do perf/quality mix at '5' and have 93 fps at 5k then you can.
I'd be interested to hear if other iMac WoW players have similar benches in testing.
Azrael.
35 degrees at idle. 1200 rpm. CPU load 0.8.
I've down loaded the disable turbo boost app. It won't disable it despite me clicking on it...and allowing it the security privileges. I enter the password to allow it to make the 'changes.'
I did have a 'violent' shut down out of no where (my 1st.) It could be to this app. The only other thing I was running was Z-Brush. Poser 11 at the time.
Azrael.
I've down loaded the disable turbo boost app. It won't disable it despite me clicking on it...and allowing it the security privileges. I enter the password to allow it to make the 'changes.'
I did have a 'violent' shut down out of no where (my 1st.) It could be to this app. The only other thing I was running was Z-Brush. Poser 11 at the time.
Azrael.
Thank you very very much for this! I had a 2017 5k iMac with the Radeon Pro 580 And I want to play at 5k window size and 5k render scale. If I had both of those set to 5k and all settings turned down to setting level 1 I would get around 47 FPS in Boralus. I did have a couple other settings turned up like view distance and ground clutter set to 10 just to help somewhat but I felt since the resolution was so high and the render scale made everything so sharp that I didn’t even need to crack up any other settings. It just looked so good even at level 1. If I dropped the render scale down to 2560x1440 it was no issue at all but you would see some 3D visuals look worse naturally.
I have WoW installed on my new iMac and wow this 5700XT isn’t even breaking a sweat lol. With window size and render scale set to 5k and all settings turned down to 1 along with ground clutter and view distance set to my previous settings of 10, I am well over 90FPS in boralus so this is a HUGE improvement. Not to mention the CPU isn’t even being used barely at all. I will say however there isn’t any fan noise for quite some time but it does ramp up to full blast when I don’t think it should. It ramped up to 2700 rpm when the GPU was being used 30% and CPU was at like 5% and temps were mid 60s Celsius. Not sure why MacOS is so aggressive with the fan speed there but it is what it is. I even tried disabling turbo boost which I did confirm that it was disabled and still same thing. This iMac is more than powerful enough to handle WoW all day which is great to see. Thanks again for all your help!
I booted my 2017 up for one last look before I erased it for sale. Temps were about the same - idling around 40, at 1200RPM albeit due to the nature of the fans in the 2017 model, the iMac was virtually silent.
I think the 2020s idle just fine albeit whatever Apple has done makes the fan louder at 1200RPM. They do however get quite hot quite quickly. I’ve never had the fans spin up in macOS (but I don’t really do heavy tasks in that side) but I do get them spun up (and down and up and down again) when playing games in Windows. I am not a fan (pardon the pun) of the fan curve in Bootcamp.
I’ve never had a panic on my 2017 i7 using the disable turbo boost app. Yes it needs admin rights. Just a data point, YMMV.
Yes. The cpu seems quick to get hot. The fans pulsing in just for browsing the Z-Brush interface is just odd.
Not sure the fan curve is great in Bootcamp. My last iMac which I played a single old game in Bootcamp can attest to that with a fried gpu.
I wouldn't put it past Apple to use a cheaper fan in the iMac. (It's not like they splashed out on the cooling on this iMac. There's a lot of unused space.). Didn't use a cheap and nasty blue plastic 'cog' to rest the heavy monitor's adjustment on.
At idle. It's very subtle. But it's there. Unless you're listening for it...you may not notice it.
I think it's just another indication that Apple are at the end of the road with Intel.
Azrael.
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With Vmware Fusion 12 releasing yesterday I downloaded it and started building my lab, which means I now have a better idea how my iMac runs under load. Today I build a Nutanix Community Edition 3 node cluster nested on top of Fusion.
At idle the fan is at 1200rpm, and I'm seeing 31db on db Meter with my iPhone sitting under the screen on the iMac stand, which is inaudible from my seat.
With the 3 VMs doing the initial configuration, I saw the CPU load hovering around 45-60%, temperatures in the 90s, fans between 1400-2100 and between 40-47db. Obviously I could hear it easily from my seat, but it wasn't loud or annoying to me. It could be a problem if I was doing audio recording, but I don't think I ever will, so not a problem for me.
At idle the fan is at 1200rpm, and I'm seeing 31db on db Meter with my iPhone sitting under the screen on the iMac stand, which is inaudible from my seat.
With the 3 VMs doing the initial configuration, I saw the CPU load hovering around 45-60%, temperatures in the 90s, fans between 1400-2100 and between 40-47db. Obviously I could hear it easily from my seat, but it wasn't loud or annoying to me. It could be a problem if I was doing audio recording, but I don't think I ever will, so not a problem for me.
I have been sitting in front of my 2020 i9 5700XT iMac all day. Can't hear the fans at all. I can hear the fans on the 15" MacBook it replaced from across the room though. My daughter is playing Minecraft on what is now her laptop.
Good thing you do not use an Xbox They make hella fan noise but that is where my games are so it is ok. I think Jobs and his Cube created an unrealistic noise expectation among mac users. Remember Steve was NUTS.
I've logged a support issue with Pixelogic (ZBrush) regarding the iMac 'fan' kicking in whilst browsing the ZBrush interface.
It's very distracting kicking in whilst doing nominal 'work' (browsing the interface? A light render? Low poly modelling?)
Nothing my 2012 couldn't do in its sleep. With no noise.
The fan kicking in for a stress test render. I can accept that. But something not quite right for the fan to be fussing over an interface.
Azrael.
I think macOS suffers from hardware acceleration optimization.
It could be due to the workforce being mostly shifted to Apple Silicon or back-end implementation of software acceleration for Apple silicon. It's not normal for a CPU to go that high for rotating a low-polygon model. This is supposed to be accelerated by GPU. Wether it's macOS with AMD drivers not optimized and not passing data to the GPU or it's the application not being optimized for Metal rendering engine. It's one of both for sure. And I can't even imagine if the application is running OpenGL underneath, macOS having phased out OpenGL effort and development for years and not giving a sh*t. And I don't think companies are focusing workforce on Metal API yet, having virtually no reference hardware to experiment with.
macOS is incredibly powerful and has incredible solid basis for graphics. I don't know why such graphics problem still occur today. There will be a pretty hard transition for anything graphics intensive (for the better!) when transitioning to Apple Silicon. But it will take time, and only once a couple of big names will show the benefits the others will jump in.
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Xcode is particular. It has incredible amount of small files to unzip/extract and to index upon installation. It's been doing this since inception (it's mostly 20 GB of disk space, not negligible).
Xcode install/updates always cause CPU usage and fans to kick on high on any Mac I've used (2015 MBP 15", 2017 MBP 15", 2015 iMac 27", 2020 iMac 27")
Yeah the iMac is horrible for any 3D work. ZBrush will turn it into a leaf blower in seconds, you only have to do the most basic operations and the fans rev up massively. If you really want to see what the fans can do, try rendering in Keyshot or Arnold. You'll be able to hear it from the next room.
I just installed the latest XCode release on my 2020 and my 2014 iMac, on both systems the fan was clearly audible during the update but the noise was not much of a difference.
If the fans kick in during high load I do not mind, as long as they are silent during normal work. I dot not have high CPU load this often and only for a short time, always a good occasion to get new coffee
If I would do hours of rendering a day the iMac Pro or the Mac Pro would probably the better choice, but for my profile I am happy with the 2020 iMac. I can not hear it while e.g. editing source code.
I'm going to try running Z-Brush on Windows 10 to compare.
My support question got an answer from Pixologic.
Enabling [Preferences
erformance:Reduce Mac Fan Activity]and...
disabling [Preferences
erformance:Optimal] then Setting the [Preferenceserformance:MaxThreads] to one less than the maximum available on their systemDeactives multidraw when not sculpting to stop the Mac fan from running constantly. (Tool tips says...in the app.). It's pretty embarrassing when an App has to have a button for that.
The noisy fan bursting in for inconsequential stuff has now disappeared.
It was hyper irritating. A low poly dog and the fan was going off on one.
It might well be down to the hyper threading and turbo behaviour. (I have the app to monitor that...but the app gives no indication that turbo boost has been turned off. I wish Apple would give users the choice to run a 10 core machine at a much lower clock. So we could get the spread of work advantage...but there's no point for the fan to be in hair dryer mode. You're just running the machine at the limit. And how long will an iMac stand that level of heat before it fries in its juices?)
I'm unimpressed with the thermal measures Apple took with this machine. Matt screen? I wish they'd bothered to put proper cooling in. A bit of under volt trickery. Lower clocks. But I don't understand ramming cpus to high clocks only to cut them down moments later as the fan kicks in. It's very distracting from what is a quietly poised machine. What's the point. Burst performance? For how long it lasts? Why bother?
Azrael.
Yeah. I wish they'd kept the Mac Pro at a sane price.
Or the iMac Pro at a more approaching price. Starting at £2999 and some might have gone for that. Rather than the eye wincing £5000 starting.
So you have to pay £5k plus to get a Mac with decent cooling. Very cynical stuff.
This machine can handle 3d in the modelling window. Seems ok (aka 5700XT.)
But rendering and the Intel cpu seems real hot and bothered. Real quick.
Just seems like the Mac OS/Intel Hardware/Developer cycle are out of sync.
One is going for Metal...the other is hot...and the other are still Open GL...which links back to Apple and Metal...
Just doesn't seem optimised across the board to me.
Azrael.
