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mathemabeat

macrumors member
Sep 1, 2009
92
52
Cincinnati, OH
I used to have a maxed out late 2012 i7 iMac. Was all but silent 99% of the time. About the only time I ever heard a peep from it was during video export in Final Cut Pro X. It got a little noisy at that point.


My current June 2017 i5 7600K, Radeon Pro 580 iMac is pretty much dead silent. Even playing games on occasion in Window10 I haven't noticed much any noise from it.
 

saberfi

macrumors member
Oct 7, 2015
87
113
I can attest that the trick mentioned here still works:

https://discussions.apple.com/message/29572550#29572550

I just did this and managed to reduce the iMac 2017 fan below 1200 rpm. I have to say that at least in my quiet computing room the difference from 1200 -> 1100 rpm is considerable to say the least. I set mine to 1050 rpm which made the fan sound disappear all together.

I have been watching youtube 1080p60 / (some) 4k for more than an hour and as far as I've noticed, the temperatures have gone up very little (1-3 degrees C) with the custom 1050 rpm profile compared to the default.

I'm quite happy with this - although naturally this requires me to remember to set the fan profile to automatic every time I intend to launch heavier apps. Most of my use is fairly light though, so I'm content.

I added the link here because Apple hasn't removed the 'trick' from their site either -- obviously adjusting the fan below 1200 rpm is at your very own risk.
 
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macsplusmacs

macrumors 68030
Nov 23, 2014
2,763
13,275
I can attest that the trick mentioned here still works:

https://discussions.apple.com/thread/7308764?tstart=0

I just did this and managed to reduce the iMac 2017 fan below 1200 rpm. I have to say that at least in my quiet computing room the difference from 1200 -> 1100 rpm is considerable to say the least. I set mine to 1050 rpm which made the fan sound disappear all together.

I have been watching youtube 1080p60 / (some) 4k for more than an hour and as far as I've noticed, the temperatures have gone up very little (1-3 degrees C) with the custom 1050 rpm profile compared to the default.

I'm quite happy with this - although naturally this requires me to remember to set the fan profile to automatic every time I intend to launch heavier apps. Most of my use is fairly light though, so I'm content.

I added the link here because Apple hasn't removed the 'trick' from their site either -- obviously adjusting the fan below 1200 rpm is at your very own risk.

what's the trick exactly?

it was a long thread. is there some sort of Fan Control app that can be installed.

apologies if i missed something obvious.
 

kingdavidd

macrumors newbie
Jun 22, 2017
11
1
so i've gone thru the whole thread and still a tad confuse: may someone help me understand what the difference is between the processor with a "K" and the one without?

and

what advantages do i gain by having 8GB of video memory vs 4

thank you!
 

EugW

macrumors G5
Jun 18, 2017
14,996
12,961
so i've gone thru the whole thread and still a tad confuse: may someone help me understand what the difference is between the processor with a "K" and the one without?

and

what advantages do i gain by having 8GB of video memory vs 4

thank you!
K is unlocked... which is totally irrelevant to Mac users. However, the K parts are faster than their non-K counterparts as well.

More important is just to know the specs of the individual chips:

i5-7500 and i5-7600 have TDP of 65 Watts
i5-7600K and i5-7700K have TDP of 91 Watts
 

Smoothie

macrumors 6502a
Jun 23, 2007
781
544
California
K is unlocked... which is totally irrelevant to Mac users. However, the K parts are faster than their non-K counterparts as well.

More important is just to know the specs of the individual chips:

i5-7500 and i5-7600 have TDP of 65 Watts
i5-7600K and i5-7700K have TDP of 91 Watts

Keep in mind that TDP does not always provide a perfect way of comparing chips. I mentioned the following in a post above.

The 7600K and the 7700K are both rated at 91 watts for TDP. TDP is not a measurement of how much power a chip uses. It's a rough measure of how much power is generated in heat by the chip so that a computer designer can come up with a good cooling solution. (There is some correlation between power used and heat dissipated.) The problem is that TDP is somewhat arbitrary, since chip manufacturers often assign the same TDP to a series of chips with different clock speeds and the existence or non-existence of hyperthreading. Clock speed and hyperthreading are major contributors to heat generation.

Although the 7600K and the 7700K have the same TDP according to Intel, the 7600K runs cooler than the 7700K. This is shown in tests where the chips are subjected to load testing. (The 7700K has a higher base clock speed and it has hyperthreading.) Less heat generation means lower fan speed. It's possible that Intel lumped the 7600K and the 7700K together regarding TDP because the "K" signifies that the chips have an unlocked multiplier which allows a user to overclock the chips. Apple does not provide for overclocking.
[doublepost=1498684784][/doublepost]
what advantages do i gain by having 8GB of video memory vs 4

thank you!

8 GB of VRAM should provide better frame rates in games that rely on a graphics chip. It should also help with virtual reality.
 

Ph.D.

macrumors 6502a
Jul 8, 2014
553
479
I can attest that the trick mentioned here still works:

https://discussions.apple.com/message/29572550#29572550

I just did this and managed to reduce the iMac 2017 fan below 1200 rpm. I have to say that at least in my quiet computing room the difference from 1200 -> 1100 rpm is considerable to say the least. I set mine to 1050 rpm which made the fan sound disappear all together.

Indeed, this works. And WOW, what a difference it can make!

For my base I5 (3.4GHz, 570GPU, 512SSD), the temperatures remain perfectly fine during every-day tasks, increasing only 2-3 degrees C, and the reduced noise is absolutely marvelous! It's clear that the fans are set very conservatively, at least for the lower-wattage models.

But: HUGE WARNING! Do not leave it on "constant RPM value" lest you forget to turn it back to auto! Monitor your temperatures carefully. If you must do this, set it to "sensor based value" (choose "CPU PECI," perhaps) and set your minimum and maximum temperatures wisely. Screw this up, launch a game, and watch your computer melt!

I'd be quite interested in learning how these programs manipulate the fan speeds. Write to me if you have some clues.
 

badlydrawnboy

macrumors 68000
Oct 20, 2003
1,531
418
I'm using my 2014 i7 4.0 Ghz right now. Just Chrome, Polymail, Slack and a few other productivity apps open. CPU says 67 degrees. Fan is at 1600 rpm according to iStat and it is clearly audible. I have a 512 GB SSD so I know it isn't the drive.

Is this expected?
 

Ph.D.

macrumors 6502a
Jul 8, 2014
553
479
I'm using my 2014 i7 4.0 Ghz right now. Just Chrome, Polymail, Slack and a few other productivity apps open. CPU says 67 degrees. Fan is at 1600 rpm according to iStat and it is clearly audible. I have a 512 GB SSD so I know it isn't the drive.

Is this expected?

What's your CPU percentage? (Those temps and the fan speed are well within normal limits, at least.)
 
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Floris

macrumors 68020
Sep 7, 2007
2,382
1,478
Netherlands
Might just be a defective iMac and could be replaced for free. Do a demo of the iMac Pro in 2018. Get the 18-core model. See if it is the same noise level. If the maximum sound from the fans is the same as your video, I will get one and if the memory and storage is easy to replace.
Do you have the iMac yourself?
I went to the Apple store and loaded up their iMacs and stress tested it, the same noise on all, jst like at home. Sounds hte same as the noise in the video.
 

petemc

macrumors member
Jan 26, 2005
37
0

propower

macrumors 6502a
Jul 23, 2010
731
126
Do you have the iMac yourself?
I went to the Apple store and loaded up their iMacs and stress tested it, the same noise on all, jst like at home. Sounds hte same as the noise in the video.

I have i5 base and i7 right now. i7 runs fan at max when loaded more than 35% CPU, i5 never goes above 70degC or ramps fans off of 1200 rpm.
[doublepost=1498694738][/doublepost]
Basically high end i7 chips run hotter and the fan is on more? My options being to return this and go for i5 or just live with it?

I wanted the highest CPU as I work with 36 megapixel images and exporting takes time. This iMac was supposed to speed up my day to day photo editing. Hmm.

Been working with Base i5 - just ordered same with 512 SSD - i7/1TB SSD BTO goes back this week.
 

badlydrawnboy

macrumors 68000
Oct 20, 2003
1,531
418
What's your CPU percentage? (Those temps and the fan speed are well within normal limits, at least.)

Just got home, woke iMac from sleep. Fan is inaudible unless I put my ear close to the computer. Temp at 44, fan at 1193, CPU at 90% idle, 4% system, 5% user.

Earlier when fan was at 1600 and completely audible I think CPU was still 80-85% idle, but I'm not sure. I'll check again and report back once the fan starts up again.
 

EugW

macrumors G5
Jun 18, 2017
14,996
12,961
I have i5 base and i7 right now. i7 runs fan at max when loaded more than 35% CPU, i5 never goes above 70degC or ramps fans off of 1200 rpm.
[doublepost=1498694738][/doublepost]

Been working with Base i5 - just ordered same with 512 SSD - i7/1TB SSD BTO goes back this week.
How did you manage to demo them anyway? Workplace? Nice to have that opportunity.

My i7-7700K went back today. My i5-7600 was ordered this morning. It will be interesting see how much difference there is between your 7500 and my 7600. Most PC reviews have the 7600 as quite cool, which isn't surprising since it's a 65 W TDP chip, but there is variability from chip to chip of course.

BTW, a few sites are claiming the TDP of both the 570 and 575 are 120 W, while the TDP of the 580 is 150 W. So I figured I may as well give the 575 a shot. However, I am thinking these are numbers for the PC parts. It seems the Radeon Pro 580 is actually a downclocked desktop RX 580, so the power usage should be lower than the PC counterpart, but I cannot find clear info on this.
 

aminadab

macrumors regular
May 3, 2005
132
1
Portland, Oregon
For what it's worth, I've had the 21.5" i7 for a full day and can report no noise at all.

This machine replaced my 2015 MBP. The most intensive task I do is edit/master high sample rate nature recordings in Logic Pro. So, my usage is very light. Nevertheless, the MBP would frequently heat up when using a high resolution Spectral Analyzer plug in. The noise was really distracting and made working with quiet nature recordings very difficult. I'm pretty sure that the thermal culprit was the discreet graphics card, however I never conducted any proper test like some have in this thread.

Also of note is my computer's position: unlike some, I don't have it against a wall. Rather, it sits in the middle of my room. Acoustics is a notoriously difficult thing to pin down, but I wonder if having the machine right up against a wall, or very near it, might compromise its thermal envelope in addition to amplifying certain frequencies as they reflect and resonate against the wall. This is, of course, just a wild speculation.

In any case, I can say that I'm super sensitive to fan noise and am very happy with this effectively silent machine. Hell, I've even opened the Photos app and have found no noise at all when quickly scrolling through photos. Such a task would make the MBP sound like a small helicopter.
 

jerwin

Suspended
Jun 13, 2015
2,895
4,652
When is PowerGadget coming out for Kaby Lake?
That's really the best way to answer these questions.
 

EugW

macrumors G5
Jun 18, 2017
14,996
12,961
For what it's worth, I've had the 21.5" i7 for a full day and can report no noise at all.

This machine replaced my 2015 MBP. The most intensive task I do is edit/master high sample rate nature recordings in Logic Pro. So, my usage is very light. Nevertheless, the MBP would frequently heat up when using a high resolution Spectral Analyzer plug in. The noise was really distracting and made working with quiet nature recordings very difficult. I'm pretty sure that the thermal culprit was the discreet graphics card, however I never conducted any proper test like some have in this thread.

Also of note is my computer's position: unlike some, I don't have it against a wall. Rather, it sits in the middle of my room. Acoustics is a notoriously difficult thing to pin down, but I wonder if having the machine right up against a wall, or very near it, might compromise its thermal envelope in addition to amplifying certain frequencies as they reflect and resonate against the wall. This is, of course, just a wild speculation.

In any case, I can say that I'm super sensitive to fan noise and am very happy with this effectively silent machine. Hell, I've even opened the Photos app and have found no noise at all when quickly scrolling through photos. Such a task would make the MBP sound like a small helicopter.
The i7 in the 21.5" is the 7700, which is 65 Watt TDP chip, and in real world testing it not surprisingly will usually run cooler than the 91 Watt TDP 7600K.

It's too bad this is not available in the 27", because it's actually faster than the 7600K. If the 7700 had been available in the 27", I might have gotten that instead. But since it is unavailable in the 27", I got the 7600, which is usually cooler than both the 7600K and the 7700.
 
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mcomp112

macrumors regular
Jan 1, 2017
111
28
For what it's worth, I've had the 21.5" i7 for a full day and can report no noise at all.

This machine replaced my 2015 MBP. The most intensive task I do is edit/master high sample rate nature recordings in Logic Pro. So, my usage is very light. Nevertheless, the MBP would frequently heat up when using a high resolution Spectral Analyzer plug in. The noise was really distracting and made working with quiet nature recordings very difficult. I'm pretty sure that the thermal culprit was the discreet graphics card, however I never conducted any proper test like some have in this thread.

Also of note is my computer's position: unlike some, I don't have it against a wall. Rather, it sits in the middle of my room. Acoustics is a notoriously difficult thing to pin down, but I wonder if having the machine right up against a wall, or very near it, might compromise its thermal envelope in addition to amplifying certain frequencies as they reflect and resonate against the wall. This is, of course, just a wild speculation.

In any case, I can say that I'm super sensitive to fan noise and am very happy with this effectively silent machine. Hell, I've even opened the Photos app and have found no noise at all when quickly scrolling through photos. Such a task would make the MBP sound like a small helicopter.


The i7 in the 21.5 inch is the 7700 (non-K), which has a TDP of 65W.
https://ark.intel.com/products/97128/Intel-Core-i7-7700-Processor-8M-Cache-up-to-4_20-GHz

The i7 in the 27 inch is the 7700K, which has a TDP of 91W and much higher clock speeds.
https://ark.intel.com/products/97129/Intel-Core-i7-7700K-Processor-8M-Cache-up-to-4_50-GHz

The former, therefore, runs much cooler than the latter.
[doublepost=1498703241][/doublepost]
The i7 in the 21.5" is the 7700, which is 65 Watt TDP chip, and in real world testing it not surprisingly runs cooler than the 91 Watt TDP 7600K.

It's too bad this is not available in the 27", because it's actually faster than the 7600K. If the 7700 had been available in the 27", I might have gotten that instead. But since it is unavailable in the 27", I got the 7600, which is cooler than the 7600K and which likely is also cooler on average than the 7700.

The 7600 is cooler than the 7700. I would've still preferred a 7700 though, if the option was there and especially if it came with the 580.

7700 power consumption: http://www.tomshardware.com/reviews...i7-7700k-i7-7700-i5-7600k-i5-7600,4870-9.html

7600 power consumption: http://www.tomshardware.com/reviews...7-7700k-i7-7700-i5-7600k-i5-7600,4870-11.html
 

Moriarty

macrumors 6502
Feb 3, 2008
436
208
How did you manage to demo them anyway? Workplace? Nice to have that opportunity.

My i7-7700K went back today. My i5-7600 was ordered this morning. It will be interesting see how much difference there is between your 7500 and my 7600. Most PC reviews have the 7600 as quite cool, which isn't surprising since it's a 65 W TDP chip, but there is variability from chip to chip of course.

BTW, a few sites are claiming the TDP of both the 570 and 575 are 120 W, while the TDP of the 580 is 150 W. So I figured I may as well give the 575 a shot. However, I am thinking these are numbers for the PC parts. It seems the Radeon Pro 580 is actually a downclocked desktop RX 580, so the power usage should be lower than the PC counterpart, but I cannot find clear info on this.

My 580 draws around ~105 W when gaming. If you look at the ratio of GFLOPS to core count, the 570 and 575 must be clocked lower than the 580's 1200 MHz, so those figures are way off.

This is much less power draw than the 2015 models...
 

petemc

macrumors member
Jan 26, 2005
37
0
I definitely value quietness, but also appreciate speed for exporting 36mp images from Lightroom. I tested last night and general browsing of images kicked the fans up on my i7. I'm ok with fans when its exporting as I can walk away then but while I'm browsing images? Nah that seems too much.

So I'll send this i7 back and get an i5. I'm not down with all these 7600 terms. I can only go with whats listed on Apple's site. Is the 3.8GHz i5 going to be ok? Good balance of speed and cooling?

My concern is that the i7 is noticeably smoother than my old 2012 i5 and I don't want to lose that. It's nice having a computer that doesn't feel sluggish when doing the simple things like swiping Spaces or opening a Safari tab.
 

EugW

macrumors G5
Jun 18, 2017
14,996
12,961
I definitely value quietness, but also appreciate speed for exporting 36mp images from Lightroom. I tested last night and general browsing of images kicked the fans up on my i7. I'm ok with fans when its exporting as I can walk away then but while I'm browsing images? Nah that seems too much.

So I'll send this i7 back and get an i5. I'm not down with all these 7600 terms. I can only go with whats listed on Apple's site. Is the 3.8GHz i5 going to be ok? Good balance of speed and cooling?

My concern is that the i7 is noticeably smoother than my old 2012 i5 and I don't want to lose that. It's nice having a computer that doesn't feel sluggish when doing the simple things like swiping Spaces or opening a Safari tab.
For those who don't know, his i5 is this one:

http://www.everymac.com/systems/app...-i5-3.2-27-inch-aluminum-late-2012-specs.html

There are a number of factors here, including:

You have a much faster CPU. Your old one was a Core i5-3470
You have a much faster GPU. Your old one was an nVidia GeForce GTX 675MX (or 680MX)
You have either a Fusion drive or a full-on SSD. Not sure which. I don't think you said, but your old one either had a hard drive or a Fusion drive.

So without you telling us all the details, it's hard for people know for sure why the new machine is better. For maximum responsiveness though, you'll want a fast CPU and an internal SSD (not Fusion drive).

As mentioned earlier in the thread, here are the chip specs:

i7-7700K: 4.2 GHz, with Turbo Boost up to 4.5/4.4/4.4 GHz. HyperThreading support. 91 Watt TDP. Fastest by far in multi-threaded applications, but may be only a little bit faster in single-threaded applications.
i5-7600K: 3.8 GHz, with Turbo Boost up to 4.2/4.1/4.0 GHz. No HyperThreading support. 91 Watt TDP, but runs cooler than i7-7700K.
i5-7600: 3.5 GHz, with Turbo Boost up to 4.1/4.0/3.9 GHz. No HyperThreading support. 65 Watt TDP. Performance not far off 7600K.
i5-7500: 3.4 GHz, with Turbo Boost up to 3.8/3.7/3.6 GHz. No HyperThreading suport. 65 Watt TDP. Coolest of the bunch, but also the slowest.

I went with the i7-7700K, and it was silent for the vast majority of my usage, but not 100% of my usage. I decided to chase silence and sent it back and ordered the i5-7600. With a Radeon 575 and i5-7600 and SSD, I'm not really concerned about OS smoothness, although I wonder how well these new iMacs handle dual 5K screens, if I should decide to get a 5K external screen later. The 575 is faster than the 2015's top-of-the-line GPU though IIRC, even if it isn't as fast as the new 580.
 
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Huginnmuninn

macrumors regular
Oct 8, 2011
200
30
I went to the Apple store and loaded up their iMacs and stress tested it, the same noise on all, jst like at home. Sounds hte same as the noise in the video.

You must have a quiet local Apple Store. I'm in New York City and all the stores are incredibly loud (or the sounds are boomy) and you cannot ever hear anything coming from any Mac, going back to the SoHo store which opened in 2002.
 
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