Just a bit more info. I picked up a copy of Divinity: Original Sin which is graphically demanding. The highest GPU temp I have seen is 103°C and the fan was running at 2301 RPM. So far, so good.
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iMac Retina 5K disappointing: Heat and fan noise!
- Thread starter SmallDane
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Yes, that would be expected. Transcoding video is mostly CPU-based, not GPU-based. So Handbrake isn't a good GPU test.
Heat issues with i7 and AMD Graphics
The issue with heat is obvious when you have a PC tower version of these parts and know how they are put together. The 2000 series i7's used a type of "Solder" on the CPU between the die and the metal lid that covers the cpu die. The 3000 and 4000 series i7's switch to crummy thermal paste between the CPU die and its metal lid. The i7 4790K's are said to be a "refresh" to previous crummy thermal paste model i7's and use "better" less crummy thermal paste. I have the i7 4790k in a windows machine. Intel says don't go over 72c. The stock heatsink reaches 100c easy. A giant aircooler reaches 95c, and finally a Corsair H100i water cooler knocks max temp to about 72c. If I use a CPU that has "solder" between the cpu die and the metal lid on the cpu, heat transfer is much better and you will only hit 55c under max load. You can "delid" the i7's and clean off the crummy thermal paste and put good thermal paste back on, but at extreme risk to damaging it and voiding warranty.
As for the GPU...its not AMD's fault as it is more the manufacturer who figures out the cooling solution for the GPU die. I have seen instead of using good quality thermal paste on the die to tranfer heat to a heatsink some manufacturers decide to use thermal foam tape between the die and the heatsink... this doesn't transfer heat well and acts more like an insulator. I have taken Nvidia and AMD heatsinks off of many compact devices such as laptops and found this stupid foam tape. After throwing the foam tape away and reapplying good thermal paste between the GPU die and the heatsink...max GPU temps went from 100c down to 60c. You learn this stuff through tinkering and hands on experience...not from a stupid engineers recommendation or point of view.
In conclusion I don't have an iMac 5k, but if I did and I tore it completely apart and redesigned and modded its cooling solutions, I am sure I can knock off temperatures by an impressive amount, but temps will not be knocked down by leaving it in stock configuration.
The issue with heat is obvious when you have a PC tower version of these parts and know how they are put together. The 2000 series i7's used a type of "Solder" on the CPU between the die and the metal lid that covers the cpu die. The 3000 and 4000 series i7's switch to crummy thermal paste between the CPU die and its metal lid. The i7 4790K's are said to be a "refresh" to previous crummy thermal paste model i7's and use "better" less crummy thermal paste. I have the i7 4790k in a windows machine. Intel says don't go over 72c. The stock heatsink reaches 100c easy. A giant aircooler reaches 95c, and finally a Corsair H100i water cooler knocks max temp to about 72c. If I use a CPU that has "solder" between the cpu die and the metal lid on the cpu, heat transfer is much better and you will only hit 55c under max load. You can "delid" the i7's and clean off the crummy thermal paste and put good thermal paste back on, but at extreme risk to damaging it and voiding warranty.
As for the GPU...its not AMD's fault as it is more the manufacturer who figures out the cooling solution for the GPU die. I have seen instead of using good quality thermal paste on the die to tranfer heat to a heatsink some manufacturers decide to use thermal foam tape between the die and the heatsink... this doesn't transfer heat well and acts more like an insulator. I have taken Nvidia and AMD heatsinks off of many compact devices such as laptops and found this stupid foam tape. After throwing the foam tape away and reapplying good thermal paste between the GPU die and the heatsink...max GPU temps went from 100c down to 60c. You learn this stuff through tinkering and hands on experience...not from a stupid engineers recommendation or point of view.
In conclusion I don't have an iMac 5k, but if I did and I tore it completely apart and redesigned and modded its cooling solutions, I am sure I can knock off temperatures by an impressive amount, but temps will not be knocked down by leaving it in stock configuration.
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Imac and fan noise
What happened in your case? Have you a got refund?
I have same problem. Got a new iMac Retina with Intel Core i7, 16GB memory, 1TB Flash Storage and AMD Radeon R) M295X 4GB for Graphics. The fan is going crazy when I play Civ 5.
Humac (the supplier) says that there is no hardware problem. For me it is like having a car where you can not turn off the fan.
I can not live with the noise and want to get money again. What did you do?
What happened in your case? Have you a got refund?
I have same problem. Got a new iMac Retina with Intel Core i7, 16GB memory, 1TB Flash Storage and AMD Radeon R) M295X 4GB for Graphics. The fan is going crazy when I play Civ 5.
Humac (the supplier) says that there is no hardware problem. For me it is like having a car where you can not turn off the fan.
I can not live with the noise and want to get money again. What did you do?
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If you bought it in the online Apple store, you have 14 days to return it for a full refund. You don't even have to give a reason for returning.
If you bought it in a physical store, then I don't think you have the same right of return. But I'd put pressure on them and demand that you be allowed to return it since you're not satisfied.
Thanks - I am doing the best I can. But it does not seem to work.
Must confess that I can't understand they can deliver a iMac with these problems. My old iMac 27" Civ V. played without any noise. Like you wrote:
"I thought the high-end version ought to be able to handle equivalent work load at lower temps and lower fan noise."
At the very least there should be a warning on Imac retina that it is very noisy.
Must confess that I can't understand they can deliver a iMac with these problems. My old iMac 27" Civ V. played without any noise. Like you wrote:
"I thought the high-end version ought to be able to handle equivalent work load at lower temps and lower fan noise."
At the very least there should be a warning on Imac retina that it is very noisy.
As far as I know, Humac does not accept merchandise back. Your mileage may vary, of course, and you should definitely try if you so want. (Though in the Nordics, hardly anyone's mileage ever varies.)
I am sorry for you and you have my sympathy. However, you realize that it's your duty to try to learn as much as possible about the expensive things you buy BEFORE handing over your bucks.
It's hard at times, I know. Even on this forum, you will find a number of posters and Apple fanboys who accuse those who are not happily singing at and applauding the RiMac of disturbing the parade
The RiMac has a great display and its CPU is blazingly fast. For some use cases, however, the design is so bad it really hurts. The RiMac simply lacks the greatness in the design (as seen in the Mac Pro with the triangular heat core).
I had a PowerMac G4 (the loud one, the one with the psu exchange program) and an iMac 2009 dying from heat issues. I will stay away from the RiMac thank you very much.
Well, it's a first-gen Apple product. Bound to be groundbreaking but with the occasional rough edge.
Actually I got a full return. Now I am just waiting on Skylake and hopping Apple will have solved the problems with heat and noise.
If it could help, here are the temps with the 27" iMac late 2013 (i7, 780M) on full load: 9 "yes" processes and Unigine Valley 3D benchmark running at the same time.
Image
The "yes" processes only uses CPU and the Valley is not using the GPU to the fullest. What would be interesting to know is running the furmark benchmark on this configuration. This uses the GPU to the max....
I've owned my iMac 5k (32GB RAM, 4GB Video, Core i5 3.5GHz) for about a week now and I half-tempted to say, most of you whining about fan noise are well, simply whining. Granted, there might be a few out there with faulty fans, as that's the joy of mass-production. But for the most part, the noise is no louder than anything else, in-fact measuring the decibels my MacBook Pro is louder under a compared heavy load.
With all that being said, I think they did design the retina (and current iMac line) kind of bad, it seems to be sucking air in from one side of the bottom, then blowing air out from the other side. I know the '11 27" iMac would blow air out the back near the top (not sure why it brought in air). I don't understand why the new iMac line doesn't suck air from the bottom and blow it out near the top after going through channels inside, only makes sense, due to, well, heat rising.
This is coming from someone who has built high-end systems, water-cooled systems, etc. Even water-cooled systems can get pretty loud under load (radiator fan noise).
I lightly game on the 5k iMac on full resolution 5120x2880, I bumped it down to 2560x1440 (what my previous 27" iMac ran), the fans spun down some, noise still remained. I monitor the fans (and control) with iStat Pro.
Playing full screen HD videos generate no fan noise.
With all that being said, I think they did design the retina (and current iMac line) kind of bad, it seems to be sucking air in from one side of the bottom, then blowing air out from the other side. I know the '11 27" iMac would blow air out the back near the top (not sure why it brought in air). I don't understand why the new iMac line doesn't suck air from the bottom and blow it out near the top after going through channels inside, only makes sense, due to, well, heat rising.
This is coming from someone who has built high-end systems, water-cooled systems, etc. Even water-cooled systems can get pretty loud under load (radiator fan noise).
I lightly game on the 5k iMac on full resolution 5120x2880, I bumped it down to 2560x1440 (what my previous 27" iMac ran), the fans spun down some, noise still remained. I monitor the fans (and control) with iStat Pro.
Playing full screen HD videos generate no fan noise.
iMac Retina 5K disappointing: Heat and fan noise!
Your iMac doesn't meet the spec being discussed in here. Regardless...
As far as I'm aware, the i7/M295X 5K iMac is the loudest iMac (in terms of fan noise) Apple have made in several years - since at least 2009. They say it themselves on their own website.
https://support.apple.com/en-us/HT201918
Highest thermal output with lowest number of fans = fastest fan, thus loudest fan noise (with same physical design).
It's had the same cooling system and physical design since 2012 so we can directly compare with those models. 2009-2011 had three fans and lower thermal outputs - meaning the fans will run slower and create less noise. Simple physics.
Also worth noting the 5K iMac was measured to be nearly TWICE as loud (8dB louder) than the 2013 under the same load.
http://barefeats.com/imac5k9.html
Your iMac doesn't meet the spec being discussed in here. Regardless...
As far as I'm aware, the i7/M295X 5K iMac is the loudest iMac (in terms of fan noise) Apple have made in several years - since at least 2009. They say it themselves on their own website.
https://support.apple.com/en-us/HT201918
Highest thermal output with lowest number of fans = fastest fan, thus loudest fan noise (with same physical design).
It's had the same cooling system and physical design since 2012 so we can directly compare with those models. 2009-2011 had three fans and lower thermal outputs - meaning the fans will run slower and create less noise. Simple physics.
Also worth noting the 5K iMac was measured to be nearly TWICE as loud (8dB louder) than the 2013 under the same load.
http://barefeats.com/imac5k9.html
iMac Retina 5K disappointing: Heat and fan noise!
No problem. Glad it helped.
It's worth noting I immediately noticed a significant increase in fan noise coming from my 2010 iMac to my i7/M295X 5K. That's how I first found out about the throttling and heat issues after Googling "5K iMac fan noise".
Also worth noting that the machine is still a great choice for a huge number of users. We are a niche who are fussed about this stuff. There is no guarantee the next gen will be any different.
No problem. Glad it helped.
It's worth noting I immediately noticed a significant increase in fan noise coming from my 2010 iMac to my i7/M295X 5K. That's how I first found out about the throttling and heat issues after Googling "5K iMac fan noise".
Also worth noting that the machine is still a great choice for a huge number of users. We are a niche who are fussed about this stuff. There is no guarantee the next gen will be any different.
I found an easy solution for this problem. I left the M295X out of my otherwise maxed RiMac (i7, SSD, 32GB RAM) and choose the M290X. It runs about 20C cooler than the M295X in comparable situations and is only marginally slower (8-10%). In some situations where the throttling is very heavy for the M295X there is practically no difference between the two GPUs and I am feeling much better not having a chip in my iMac with over 100C operating temperature....
Under this circumstances I don't think that the 250$ premium is worth it. If somebody really needs much GPU power both cards are not the best choice and they might wait for the next gen RiMac. Because I don't play on my iMac or don't do much 3D stuff with it this is not a real problem for me. That's why I prefer the quiet and cool M290X and safe the 250$.
Under this circumstances I don't think that the 250$ premium is worth it. If somebody really needs much GPU power both cards are not the best choice and they might wait for the next gen RiMac. Because I don't play on my iMac or don't do much 3D stuff with it this is not a real problem for me. That's why I prefer the quiet and cool M290X and safe the 250$.
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It'd be nice if the internal design had changed; I suppose it'd be wishful thinking that today's (May 19, 2015) Retina iMac is any different.
Geez... I've got to stop drinking so much...
Geez... I've got to stop drinking so much...
VSync yes or no?
One question, though: When you're playing on the riMac, do you have VSync toggled on or off? As far as I know, it is a FPS limiter and should get some workload off the GPU, therefore getting the temps lower. IMHO there's no need for drawing more frames per second than the display can show after all.
One question, though: When you're playing on the riMac, do you have VSync toggled on or off? As far as I know, it is a FPS limiter and should get some workload off the GPU, therefore getting the temps lower. IMHO there's no need for drawing more frames per second than the display can show after all.
That is the answer I have been looking for, prob money saved can go to a bigger SSD
Not sure if the 4GB vs 2GB will make much different for basic computing need?
I wilk prob open lots of things at the same time, but nothing particularly heavy to run
Thanks for the useful info! Sound was a concern for me, and I almost went with the M295X thinking apple wouldn't sell us a product with such a flaw. Does the i7 have any heat or sound concerns as compared to the i5 in this case? Also, why did you go with the installed RAM instead of just upgrading to 32GB yourself?
For a 27" don't ever order RAM from Apple. 32 GB is +720 euro here in Europe. If you do it yourself you can pay ~240 euro. Do it immediately as soon you get the machine to make you sure you don't damage the screen.