2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

Started Jul 5, 2017 | Discussions
Eug Senior Member • Posts: 2,779
2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet
6

First got the iMac Core i7-7700K. Fast, but I noticed the temps would spike high really quickly under any sort of heavy load. For surfing and stuff like that it was fine, and light image editing was fine too, with the fan always locked at the minimum 1200 rpm. However, as soon as I did anything that taxed the the CPU heavily, the fan would become noticeable. Even rapid scrolling through my entire Photos database a couple of times could get the fan ramped up to moderate speeds making it fairly audible. And with video encoding, the fan would be at max in well under a minute. Unfortunately, at max, the fan is irritating.

So I returned it after hearing about people with the i5-7500 having their fan never ever speeding up.

I didn't order the i5-7500, but ordered the i5-7600 (non-K) instead, since like the i5-7500, its a 65 Watt class TDP chip. (The i7-7700 is a 91 W class TDP chip.) Fortunately, the i5-7600 behaves similarly. I did a test h.265 HEVC encode and ran it for 10 minutes. The fan stayed silent at 1200 rpm the entire time, although after those 10 minutes the CPU temp creeped up to the low 80s Celsius. Never once did the CPU power output reach 60 Watts. It fluctuated from 52-57 Watts at 100% load.

For my usage, this is preferable. It is true that for well over 9/10ths of my usage, the i7-7700K would have remained silent. I initially figured that since I don't do super heavy stuff like video encoding very often, having the fan come on once in a while in that context wasn't going to bother me too much. I thought if I was going to do an encode, I could just go for a coffee or whatever if I found the noise objectionable.

But then after thinking about it, in those instances where I'm going for a coffee run, I really don't care if the encode takes 15 minutes or if it takes 21 minutes. However, if I do come back to my desk at the 10 minute mark, I'd like the computer to be silent for the rest of the encode, or at least very near silent.

Current setup: 27" iMac Core i5-7600 / 24 GB RAM / 1 TB SSD / Radeon Pro 575

nbirkett Senior Member • Posts: 1,246
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

Eug wrote:

First got the iMac Core i7-7700K. Fast, but I noticed the temps would spike high really quickly under any sort of heavy load. For surfing and stuff like that it was fine, and light image editing was fine too, with the fan always locked at the minimum 1200 rpm. However, as soon as I did anything that taxed the the CPU heavily, the fan would become noticeable. Even rapid scrolling through my entire Photos database a couple of times could get the fan ramped up to moderate speeds making it fairly audible. And with video encoding, the fan would be at max in well under a minute. Unfortunately, at max, the fan is irritating.

So I returned it after hearing about people with the i5-7500 having their fan never ever speeding up.

I didn't order the i5-7500, but ordered the i5-7600 (non-K) instead, since like the i5-7500, its a 65 Watt class TDP chip. (The i7-7700 is a 91 W class TDP chip.) Fortunately, the i5-7600 behaves similarly. I did a test h.265 HEVC encode and ran it for 10 minutes. The fan stayed silent at 1200 rpm the entire time, although after those 10 minutes the CPU temp creeped up to the low 80s Celsius. Never once did the CPU power output reach 60 Watts. It fluctuated from 52-57 Watts at 100% load.

For my usage, this is preferable. It is true that for well over 9/10ths of my usage, the i7-7700K would have remained silent. I initially figured that since I don't do super heavy stuff like video encoding very often, having the fan come on once in a while in that context wasn't going to bother me too much. I thought if I was going to do an encode, I could just go for a coffee or whatever if I found the noise objectionable.

But then after thinking about it, in those instances where I'm going for a coffee run, I really don't care if the encode takes 15 minutes or if it takes 21 minutes. However, if I do come back to my desk at the 10 minute mark, I'd like the computer to be silent for the rest of the encode, or at least very near silent.

Current setup: 27" iMac Core i5-7600 / 24 GB RAM / 1 TB SSD / Radeon Pro 575

Interesting.  I am looking at getting a new iMac and was considering the i7 since I also use the computer for computational work which can take advantage of the i7 hyperthreading.  But, big fan noise is a worry.

Can anyone else confirm these observations?

I am also curious how you knew the CPU models.  All I see on the Apple page is '3.5GhZ quad core...i5', '3.8GHz quad core... i5' or '4.2 gHz quad core...i7' with no mention of 7500, 7600 or 7700.

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JPAlbert Regular Member • Posts: 246
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

RE: "I am also curious how you knew the CPU models. All I see on the Apple page is '3.5GhZ quad core...i5', '3.8GHz quad core... i5' or '4.2 gHz quad core...i7' with no mention of 7500, 7600 or 7700."

This has been discussed on other forums, such as forums.macrumors.com.

I believe the "entry level" 27" iMac (3.4ghz) is a 7500, and the "midrange" 27" model (3.5ghz) is the 7600. I could be wrong.

OP Eug Senior Member • Posts: 2,779
iMac 27" CPU specs

nbirkett wrote:

Interesting. I am looking at getting a new iMac and was considering the i7 since I also use the computer for computational work which can take advantage of the i7 hyperthreading. But, big fan noise is a worry.

Can anyone else confirm these observations?

These observations have been replicated by others in internet land, and they make sense because PC reviews of the 7700K vs the 7600K and 7600 have confirmed the 7700K runs very hot and the 7600 runs cool.

It seems all the 27" iMacs have the same fan setup, so for hotter temps the fans simply run faster. The fan is more than adequate at low rpm for the 7500, but for the 7700K, under heavy CPU load, the fan must go to max.

I am also curious how you knew the CPU models. All I see on the Apple page is '3.5GhZ quad core...i5', '3.8GHz quad core... i5' or '4.2 gHz quad core...i7' with no mention of 7500, 7600 or 7700.

The base and turbo boost speeds listed by Apple correspond to the standard Intel chip specs, and also, Geekbench scores incorporate the actual model number. These are the configurations:

Base: i5-7500, 3.4 GHz with Turbo Boost to 3.8 GHz.

Mid: i5-7600, 3.5 GHz with Turbo Boost up to 4.1 GHz.

Top: i5-7600K, 3.8 GHz, with Turbo Boost up to 4.2 GHz.

The mid and top tiers can be configured with the i7-7700K, 4.2 GHz, with Turbo Boost up to 4.5 GHz.

Note that the 7500 and 7600 are 65 Watt class chips, and indeed, PC tests have confirmed them to be chips that fit that spec profile. They seem to run cool (esp. the 7500).

The 7600K and 7700K are 91 Watt class chips. The 7700K achieves near that with heavy CPU load, but it's much harder according to some tests to get the 7600K up to very high.

OP Eug Senior Member • Posts: 2,779
7500 vs 7600

JPAlbert wrote:

RE: "I am also curious how you knew the CPU models. All I see on the Apple page is '3.5GhZ quad core...i5', '3.8GHz quad core... i5' or '4.2 gHz quad core...i7' with no mention of 7500, 7600 or 7700."

This has been discussed on other forums, such as forums.macrumors.com.

Yes.

I believe the "entry level" 27" iMac (3.4ghz) is a 7500, and the "midrange" 27" model (3.5ghz) is the 7600. I could be wrong.

You are correct.

salamander1 Senior Member • Posts: 1,418
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet
1

27 inch imac better cooling. 

https://www.youtube.com/watch?v=W4ldLHYTtec&t=13s

nbirkett Senior Member • Posts: 1,246
Re: iMac 27" CPU specs

Eug wrote:

nbirkett wrote:

Interesting. I am looking at getting a new iMac and was considering the i7 since I also use the computer for computational work which can take advantage of the i7 hyperthreading. But, big fan noise is a worry.

Can anyone else confirm these observations?

These observations have been replicated by others in internet land, and they make sense because PC reviews of the 7700K vs the 7600K and 7600 have confirmed the 7700K runs very hot and the 7600 runs cool.

It seems all the 27" iMacs have the same fan setup, so for hotter temps the fans simply run faster. The fan is more than adequate at low rpm for the 7500, but for the 7700K, under heavy CPU load, the fan must go to max.

I am also curious how you knew the CPU models. All I see on the Apple page is '3.5GhZ quad core...i5', '3.8GHz quad core... i5' or '4.2 gHz quad core...i7' with no mention of 7500, 7600 or 7700.

The base and turbo boost speeds listed by Apple correspond to the standard Intel chip specs, and also, Geekbench scores incorporate the actual model number. These are the configurations:

Base: i5-7500, 3.4 GHz with Turbo Boost to 3.8 GHz.

Mid: i5-7600, 3.5 GHz with Turbo Boost up to 4.1 GHz.

Top: i5-7600K, 3.8 GHz, with Turbo Boost up to 4.2 GHz.

The mid and top tiers can be configured with the i7-7700K, 4.2 GHz, with Turbo Boost up to 4.5 GHz.

Note that the 7500 and 7600 are 65 Watt class chips, and indeed, PC tests have confirmed them to be chips that fit that spec profile. They seem to run cool (esp. the 7500).

The 7600K and 7700K are 91 Watt class chips. The 7700K achieves near that with heavy CPU load, but it's much harder according to some tests to get the 7600K up to very high.

Thank you this - very informative.

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robgendreau Veteran Member • Posts: 5,097
Re: iMac 27" CPU specs

Interesting stuff; thanks for the info (I especially like the drilled out case solution...that, and maybe some more holes, would actually look pretty cool  

And the OP made an especially important point, since when shopping one can get lost in specs and processor-peeping: some tasks may be slower, but if they are unattended tasks, it doesn't matter so much. There's a big difference between waiting for the image to refresh after hitting a denoise button vs waiting for it to transcode some video or batch copy.

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joema1
joema1 Contributing Member • Posts: 691
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

nbirkett wrote:

.... I am looking at getting a new iMac and was considering the i7 since I also use the computer for computational work which can take advantage of the i7 hyperthreading. But, big fan noise is a worry.

Can anyone else confirm these observations?

Apple's specs say the 2017 iMac 27 with i7 uses less power (hence produces less heat) than the equivalent 2015 model. So whatever the 2017 model does regarding noise and heat, it should be no worse than the 2015 model.

I have a 2015 top-spec iMac 27 and will be getting a 2017 model next week. I'll do thorough side-by-side video encoding tests, including performance, fan noise and temps.

In this review, the 2017 iMac 27 i7 was significantly cooler and quieter than the 2015 model, but it focused on GPU stress not CPU stress: https://www.youtube.com/watch?v=rdQBoXNyxnY&t=2s

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ArtAlt
ArtAlt Senior Member • Posts: 1,917
Re: iMac 27" CPU specs

robgendreau wrote:

Interesting stuff; thanks for the info (I especially like the drilled out case solution...that, and maybe some more holes, would actually look pretty cool

And the OP made an especially important point, since when shopping one can get lost in specs and processor-peeping: some tasks may be slower, but if they are unattended tasks, it doesn't matter so much. There's a big difference between waiting for the image to refresh after hitting a denoise button vs waiting for it to transcode some video or batch copy.

I remember reading that when the cpu gets hot it automatically throttles down its speed.

Could it be that the higher powered chip ends up running SLOWER because it's a higher power draw and generates more heat under similar loads?

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joema1
joema1 Contributing Member • Posts: 691
Re: iMac 27" CPU specs
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ArtAlt wrote:

...I remember reading that when the cpu gets hot it automatically throttles down its speed.

Could it be that the higher powered chip ends up running SLOWER because it's a higher power draw and generates more heat under similar loads?

This won't happen, esp. on the 2017 iMac 27. As shown in the above video at 03:15, the 2017 iMac 27 i7 is cooler under high CPU loads than the 2015 i7 model. It is also cooler under high GPU loads.

In those tests the 2017 iMac 27 i7 did not slow down much at all under sustained transcoding loads. Depending on the software it is about 40% faster than the 2017 i5 model. About 10% of this from CPU clock speed and 30% from hyperthreading benefit. So even if it slowed down 1% that still makes the i7 model it 39% faster than the i5 for that workload.

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rlodina New Member • Posts: 1
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

joema1 wrote:

I have a 2015 top-spec iMac 27 and will be getting a 2017 model next week. I'll do thorough side-by-side video encoding tests, including performance, fan noise and temps.

Hi joema1.

Do you have some news to share with us regarding 2017 i7 fan noise.

Thank you

joema1
joema1 Contributing Member • Posts: 691
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

rlodina wrote:

joema1 wrote:

I have a 2015 top-spec iMac 27 and will be getting a 2017 model next week. I'll do thorough side-by-side video encoding tests, including performance, fan noise and temps.

Hi joema1.

Do you have some news to share with us regarding 2017 i7 fan noise.

Thank you

Yes I have tested it extensively and have it and m 2015 i7 iMac 27 on my desk side-by-side. I also have a top-spec 2013 i7 iMac 27. I can tell no major difference in the noise or fan behavior between the 2013, 2015 or 2017 i7 iMac 27. This is using a variety of software, but especially FCPX and Lightroom.

The idea that the 2017 iMac i7 is somehow unusually loud or different than past models within the past four years is not correct.

However any of the i7 iMacs from 2013 onward (and maybe 2012, I haven't tested that) can spin up fans if under sustained high CPU load.

This is not unique to the iMac or due to the thin all-in-one design. I have a Windows workstation with Noctua NH-D14 CPU cooler, Noctua case fans, and slow-turning 200mm case fast all tied to a fan controller. If I run Prime95 and the GPU stress test Furmark, it also gets loud, despite the big case and all the "quiet" fans.

There is some evidence the 2017 i5 iMac 27 is pretty fast and may run considerably quieter. It has a 3.8Ghz CPU which turbos to 4.2Ghz, so it is pretty fast despite not having hyperthreading. In my limited tests hyperthreading does not benefit Lightroom -- you can enable/disable that feature using the 3rd party utility CPUSetter.

As a video editor I need the fastest possible machine and the relatively infrequent fan noise from my 2017 i7 iMac is not a big deal -- my desk is stacked with spinning Thunderbolt RAID arrays, so there is always background noise happening.

However if you are sensitive to noise, have a quiet household HVAC system and no other competing background noise, AND if you do sustained CPU-intensive tasks on an i7 iMac, it might bother some people. Just doing a lot of rapid work with the Lightroom correction brush on 38+ megapixel raw stills can cause it.

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DFPanno
DFPanno Veteran Member • Posts: 5,475
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

My 2017 27" i7 iMac's fan will come up on occasion.

Rapidly sorting images in Photo Mechanic or using brushes in LR will start it.

Not too loud; just there if you will.

Don't really notice it at this point.

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Cica114 New Member • Posts: 1
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet

Thank you all for this discussion!

I do NOT have a problem with fan noise, as my 10 year old workhorse the Mac Pro 1.1 has really heavy noise, when it`s spinning up.

But:

I was, am, kind of really shocked by the CPU temperatures of the Imac 27inch 4.2 (mid 2017) I have 8GB of Ram and the FusionDrive 2TB

Simple browsing through my Lightroom library gets the CPU jump up to 100Degrees(according to Mac fans control)

https://www.crystalidea.com/macs-fan-control

It goes down quite quickly afterwards...but is this normal....or do I have a faulty Chip?

Apple support could not be helpful, the Hardware test says my computer is ok.

Can one or more of you users of the 4.2 7i users do me the favor and run the CPU Cinebench-Test and show me the temperatures of your chips in the middle or the ending of the test rendering? That would be sooo helpful for me! https://www.maxon.net/de/produkte/cinebench/

Thanks for help in advance! and excuse my english!

OP Eug Senior Member • Posts: 2,779
Re: 2017 iMac: i7-7700K hot & loud, i5-7600 cool & quiet
1

DFPanno wrote:

My 2017 27" i7 iMac's fan will come up on occasion.

Rapidly sorting images in Photo Mechanic or using brushes in LR will start it.

Not too loud; just there if you will.

Don't really notice it at this point.

This type of behaviour drove me nuts. But I don't need all that power so I was happy to downgrade the CPU.

mrmut
mrmut Contributing Member • Posts: 611
2017 iMac TDP comparison

I am just in the process of buying a 2017 27" mac, and noise produced is a major issue. This thread was most helpful.

There are essentially two choices:

3.4 and 3.5 models: CPU 65W TDP, GPU 120W TDP

3.8 and 4.2 i7 models: CPU 91W TDP, GPU 197W TDP

Difference is very big; over 100W (103) of additional heating you need to dissipate, and the cooling system is the same.

If you work in an office, you will probably never notice, or will only barely notice the fans. But in quiet working or home environment, the noise produced will get plenty loud.

The speed provided by the 3.4 and 3.5 models is adequate for almost anything you might need to do on the computer for a very long time, and those who will need the additional power, will know it.

So, purchase accordingly.

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MGRS
MGRS New Member • Posts: 17
Re: 2017 iMac TDP comparison

mrmut wrote:

I am just in the process of buying a 2017 27" mac, and noise produced is a major issue. This thread was most helpful.

There are essentially two choices:

3.4 and 3.5 models: CPU 65W TDP, GPU 120W TDP

3.8 and 4.2 i7 models: CPU 91W TDP, GPU 197W TDP

Difference is very big; over 100W (103) of additional heating you need to dissipate, and the cooling system is the same.

If you work in an office, you will probably never notice, or will only barely notice the fans. But in quiet working or home environment, the noise produced will get plenty loud.

The speed provided by the 3.4 and 3.5 models is adequate for almost anything you might need to do on the computer for a very long time, and those who will need the additional power, will know it.

So, purchase accordingly.

I am considering moving to iMac 2017 27" from my current Windows system since I face lot of issues openning heavy photo files (80-90MB) and/or see them on screen as thumbnails. After reading all of this thread I am wondering whether to buy a i5 (and which) or i7 machine. Would the i5 be sufficient for working on such heavy files? I am working mainly with Lighroom and rarely Photoshop.

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mrmut
mrmut Contributing Member • Posts: 611
CPU speed comparisons %

MGRS wrote:

I am considering moving to iMac 2017 27" from my current Windows system since I face lot of issues openning heavy photo files (80-90MB) and/or see them on screen as thumbnails. After reading all of this thread I am wondering whether to buy a i5 (and which) or i7 machine. Would the i5 be sufficient for working on such heavy files? I am working mainly with Lighroom and rarely Photoshop.

I will give you a comparison that helped me. There are two benchmark processors that I use for comparison: Core 2 Duo 2.4 ghz and AMD Phenom II 1090T.

First one is sufficient for normal work for many years now, and I have it on my MacBook Pro 2008 (10 years old!!! and working!), and similar CPU in many other office computers i maintain.

1090T is on my work PC. That one is sufficient for anything at all, from gaming, to photo editing, including very big stuff. AMD is a base CPU.

Passmark comparison:

  • Core 2 Duo 2.4 - 1539
  • AMD 1090T - 5613 - BASE
  • Intel Core i5-7500 3.4 - 8103 = +44% base
  • Intel Core i5-7600 3.5 - 8890 = +58% base
  • Intel Core i5-7600K 3.8 - 9233 = +64% base
  • Intel Core i7-7700K 4.2 - 12106 = +115% base

As you can see, differences are humongous, especially so with i7. Mind that just 10-20% increase in total CPU speed is a lot.

So, performance wise, you will be fine with any of the 27" macs. They are all very powerful machines, and combined with fastest available SSD-s (Apple pushed standard), your files will work well. You also have decent GPU on all of them.

If we would compare these iMac 27" with cars, that would be 200 HP car, 250 HP car, 300 HP one and 400 HP one. 200 HP car moves great. 250 is better. 300 HP is fantastic, and 400 HP one will leave you breathless.

In the end, you will also have to consider TDP. There is significant TDP increase with move to 3.8 or i7 version, both in CPU and GPU. I would say that if you are going for 3.8 version, you should get an i7.

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mrmut Contributing Member • Posts: 611
2017 iMac i5-7600 is an optimal iMac
6

I just ordered iMac 2017 27" 3.4 (i5-7600) with Radon Pro 575 GPU and 512 RAM.

I deliberated this purchase for quite some time, as in my country you can not return the purchase, or exchange the machine for another. What you buy is what you get (except if something is broken).

Here is some reasoning for other people that might be going through the same process.

**

First of all I would like to say that I was not bound with budget. I could get any configuration I wanted, but there were some obvious issues. Reading first post by OP will shed some light to the issue. This comment will talk mainly about GPU, CPU and noise/heat issues. SSD is a must, and size whatever you need.

Generally I wanted the i7 model with Pro 580 GPU. But as I am very sensitive to noise, and work in very quiet environment, noisy fans are unacceptable.

Reading many threads online, I focused on audio studio guys comments, as they are the most sensitive to noise in their workflow and they will be the ones to objectively comment on the issues. It is generally accepted that:

i5-7500 (3.4) and i5-7600 (3.5) with Radeon Pro 570 and 575 are essentially noiseless. Both machines have the same TDP, and one will be hard pressed to actually notice any difference between the two. I have personally tortured 3.4 version with 1TB disk, and can confirm that is practically impossible to get the fans go higher than say 1400 (1200 is base). This was after an hour of "yes", geekbench, and GPU torture at the same time.

I have NOT been able to test the i7 or 3.8 i5 machines, but thermodynamics is what it is. Every 27" iMac has exactly the same heat management system. On 3.8 version it is essentially at the maximum, and with i7 version it is underpowered.

Generally TDP values move this way (CPU + GPU):

3.4 and 3.5 - 185W

3.8 and i7 4.2 - 241W

There is also the issue of CPU speed related heat. Both 3.5 and Pro 575 GPU will heat a bit more than on 3.4 and Pro 570 but the difference is negligible (OP mentions this too).

On 3.8, Pro 580 and 4.2 i7 difference is very big. Sound processing guys report that both on 3.8 and 4.2 CPU you need to turn off turbo boost, and on i7 even hyper threading to be able to work in silence.

Why is this "noise" such a big deal? Because there is a lot of it. At idle, any iMac is practically silent. But when you start working, and mac heats up, fans will spin up, and it will start to annoy you. Take a look at this:

https://youtu.be/eqE7lM4KB2c?t=3m32s

As you can see, noise that iMac can make is nothing to sneeze at.

There are also some other issues with iMacs that are generally not talked about: system cooling headroom. With time, dust creates a film of dust on iMac fans. It was not easy to clean that dust on old iMacs (you had to remove the screen), and it is certainly not easy now when the screen is glued on.

Having some headroom in the cooling department will help fight this inevitable problem with time.

And now, performance:

Essentially, the cost difference between any of the 27" iMacs is relatively insignificant, because any of them is expensive, and they are usually used mainly for business purposes, so the costs are perceived differently.

So, what kind of performance difference is between the 27 iMacs?

It goes like this:

  • 3.4 - very fast machine, will do everything you need
  • 3.5 - about 10% faster, it has faster GPU, optimal choice
  • 3.8 - in practical use CPU is marginally faster, but this model has faster GPU than 3.5 model
  • 4.2 i7 - very fast CPU, very fast GPU

Now, how do all these compare, and why is there almost no difference between 3.8 and 3.5 CPUs?

Well, the 3.5 (and 3.4) are 60W TDP, and 3.8 is 90W unit. They all have a thing called turbo boost, that makes the CPUs work on higher clock than base, until they get heated up. Guess which one heats up faster? This means that while 3.8 unit has faster base clock and faster core speed, it will perform at about the same level like 3.5 when entire CPU is taken into account, because the turbo boost speed will need to throttle down:

Total CPU speed difference; it is not +156W but +56W, my mistake.

So what about GPU and gaming (admit it)? Do you get a lesser model with 570 and 575 vs 580? Well, yes, you do. In a way. All GPUs used on 27" iMacs are VERY fast. They all surpass every except the fastest Mac Pro models, and you will be able to game fluidly with any of them.

Pro 570 is able to run anything at all, at ultra in 1080p, and achieve 50-60 framerate with ease. You *will* be able to run fair number of games in 2k+ resolutions. There are many YouTube videos of iMac 27" 570 gaming.

Pro 575 does the same as 270 with about 10-20% performance increase. This means you will be able run any game at all in 1080p in Ultra, and also run some stuff comfortably (30-40 frames) in 2k, 4k and even 5k at max settings.

Pro 580 is faster additional 10-20%. That means more games in high resolutions at Ultra.

Unfortunately, 580 Pro is a 150W GPU, and comes with 90W CPU.

There is also a question of how much you actually play games, and does it make any sense to withstand increased noise constantly for the sake of casual gaming.

There is also the eGPU solutions Apple announced. The feature is in the works currently, and it is expected to be fully working in a few months - half a year. That will enable you to mount a really powerful GPU, ie Radeon Vega externally and do whatever you want (including 5k ultra gaming at gazillion fps) when you need the power. Vega 64 is more than 100% more powerful than Pro 580.

GPU compute comparisons:

Pro 575 is in red box.

So. In my view, 3.5 version with 575 GPU is a performance and comfort sweet spot. OP came to the same conclusion.

Good luck guys!

 mrmut's gear list:mrmut's gear list
Olympus E-1 Olympus E-450 Olympus E-M1 Olympus Zuiko Digital ED 8mm 1:3.5 Fisheye Olympus Zuiko Digital ED 50mm 1:2.0 Macro +3 more
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