Dunno about you but my home does not have the same temperature as outside. It is much warmer inside, somewhere around 20 to 21C. Same thing can be said when it is warm outside. The only problem is on the very few days the temp does go up high. For that there is air-con plus you usually are not that very active. In reality the problem of heat isn't as big as you think.
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My iMac i7 runs too hot!
- Thread starter Moriske
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Your system was designed to run as it is, so no worries.
If this is really a big concern for you, than the low tech solution is to run a small fan, while you're doing heavy encoding. Back when I used to do a lot of Handbrake, I'd always queue up a big batch to run at a time when I wasn't sitting in front of my system. It'd get hot and loud, which is the nature of the beast. But I noticed that when I ran a very small fan on the back of the system, things would cool down considerably. And the noise of the fan was a lot quieter than the sound from the internal fans.
A low-tech $20 solution to ease your mind on the longevity of your $3,000 purchase. Again, not really necessary, but it's an option. And you don't need much of a fan - I've even heard of people running those little USB powered fans in the back of their iMacs. Only time you'd even need to think about this is when you've got a big batch encoding. It's amazing how much of a difference a tiny bit of airflow will make.
People rarely consider outside airflow with these sorts of situations. I once had a friend who's iMac ran loudly, but she had it sitting in a secretary cabinet, pretty much surrounded by wood. When she cranked it up, it ran like a heater pushing hot air into warm air, until the temp spiked. Sliding it out a couple inches made a big difference (we wound up getting her a small fan, since she still wanted to be able to hide her system in the cabinet. Similar situation with people who place their systems in corners, where there's not much airflow. There's a reason people working in datacenters wear sweaters year-round.
If this is really a big concern for you, than the low tech solution is to run a small fan, while you're doing heavy encoding. Back when I used to do a lot of Handbrake, I'd always queue up a big batch to run at a time when I wasn't sitting in front of my system. It'd get hot and loud, which is the nature of the beast. But I noticed that when I ran a very small fan on the back of the system, things would cool down considerably. And the noise of the fan was a lot quieter than the sound from the internal fans.
A low-tech $20 solution to ease your mind on the longevity of your $3,000 purchase. Again, not really necessary, but it's an option. And you don't need much of a fan - I've even heard of people running those little USB powered fans in the back of their iMacs. Only time you'd even need to think about this is when you've got a big batch encoding. It's amazing how much of a difference a tiny bit of airflow will make.
People rarely consider outside airflow with these sorts of situations. I once had a friend who's iMac ran loudly, but she had it sitting in a secretary cabinet, pretty much surrounded by wood. When she cranked it up, it ran like a heater pushing hot air into warm air, until the temp spiked. Sliding it out a couple inches made a big difference (we wound up getting her a small fan, since she still wanted to be able to hide her system in the cabinet. Similar situation with people who place their systems in corners, where there's not much airflow. There's a reason people working in datacenters wear sweaters year-round.
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Actually a Raspberry Pi 2 is even cheaper...
The comparison was between the nMP and the iMac 5K, not the PC because it is not a Mac. If you look at the Apple website you can see the prices where the nMP costs more than the iMac but it also holds more computing power. Since we are comparing it to the iMac 5K that means we also need to add a 5K display to the mix. The only other 5K display currently available is from Dell and that one costs almost the same as the iMac 5K. So there you go, almost twice the price for a similar 5K config with a Mac Pro.
Different machines, different price ranges, different expectations.
If u do these kinda tasks regularly, you must have a high demand for computer performances. You should be looking for a replacement in about 3 years.
Within 3 years, just buy apple care, if cup ever burns out, you get a new one.... What's there to worry about.
Yes, high temp certainly affect the lifespan of any electronics, but engineers at Apple must have made sure that this temp won't have an actually noticeable affect to your system within 3 years.
Within 3 years, just buy apple care, if cup ever burns out, you get a new one.... What's there to worry about.
Yes, high temp certainly affect the lifespan of any electronics, but engineers at Apple must have made sure that this temp won't have an actually noticeable affect to your system within 3 years.
I definitely choose the AppleCare
This looks like a good idea
I hope this will give a better cooling and noise control on my new iMac next week.
Can you tell me how to put it on my iMac?
A better example than this?
I don't think you need to get overly complex about it. Any old tiny fan will do. There are some cheap USB powered ones in the $10 range that should be adequate. I've even seen some blade-less designs (ala Dyson) that are supposed to be quiet, under $20. Point is just to ensure the the warm air doesn't get trapped behind your system.It doesn't need to be on the iMac, just in a position where it can help air flow past it.
I definitely choose the AppleCare
This looks like a good idea
I hope this will give a better cooling and noise control on my new iMac next week.
Can you tell me how to put it on my iMac?
A better example than this?
Actually it was a comparison of 'My PC' rather than 'A PC'., but the point was any computer that has sufficient cooling (i.e. isn't an all in one like the iMac or a very small platform like a NUC or Mac Mini) won't overhead while being pushed. I mentioned my nMP doesn't have this over heating issue, nor does my PC. It doesn't matter whether it's a Mac or not, it doesn't overheat. The iMac does overheat though and this is why I said it's a piece of crap. It wasn't an iMac vs nMP thing, but 'all in one computers don't have proper cooling' thing.
And by the way the Dell 5K display is cheaper than the iMac, even the base level one - Dell 5K monitor £1200, 5K iMac £1500. Not much in it agreed, but the spec of the iMac in this post is around £3000. Yes the nMP is more, mine cost just over £4000 and I got a Dell 4K monitor (£500) because all of the 5K monitors are glossy and unless I use a magnifying glass I can't see the difference between 4K and 5K. £1500 difference, but much more usable. The PC cost around £1500. It's old now, but can game at 1440p with all settings on ultra in games like Skyrim, without overheating.
So I honestly don't care about any comparison with the iMac and nMP because the iMac would be too noisy to live with when pushed so it's not even a viable option for any serious work. Pretty to look at yes, can I run heavy workloads on it, no.
The I clearly must have a faulty iMac 5K as it doesn't overheat... The only thing overheating are the people who do not have the iMac 5K and go off on numbers alone. Don't be this overdramatic about heat. For the hardware that is in the machine the temps are within specs. It's just not for all kinds of workloads but neither is any other machine be it Mac or PC.
Talking about heavy workloads...the nMP would be underpowered for those as well and make a lot of noise because it is being pushed to its extremest. For actual heavy workloads you are looking at multi-core, multi-cpu machines up to even multi-node configurations. If you can run it on a single cpu, multi-core machine then it is not a heavy workload. So yes, the Macs are pretty to look at but unsuited for any actual heavy workloads as are any of their PC competitors.
That's the entire problem here: people are using the wrong kind of hardware for certain workloads, they are expecting to run every possible workload on certain hardware (no matter if Mac or PC) which is incorrect because you can't. iMacs aren't suited for all workloads and neither is the nMP or any other PC. When pushing any of such hardware you'll run it at the max and it will be noisy and hot. That's just physics. Another thing is definition: what you consider a heavy workload might be out of the ball park for someone else and a light workload for another. The fact that things like memory and cpu usage is at its max doesn't mean there is a heavy workload. There are quite a lot of workloads that simply use everything if possible. Whenever you run something else alongside it, it will return system resources. Take a look at how load of a machine is calculated in UNIX/Linux systems and you'll understand what I mean by this (which is not for the faint hearted btw!).
And btw, if you meant to compare it to a PC then don't compare it to an nMP at all. If you do a comparison between the iMac 5k and nMP or a PC you need to keep the specs the same. This also means that you need to use a 5K display for the nMP or PC setup. If not then you might as well compared it to a Raspberry Pi 2 since you are comparing apples and oranges anyway.
Talking about heavy workloads...the nMP would be underpowered for those as well and make a lot of noise because it is being pushed to its extremest. For actual heavy workloads you are looking at multi-core, multi-cpu machines up to even multi-node configurations. If you can run it on a single cpu, multi-core machine then it is not a heavy workload. So yes, the Macs are pretty to look at but unsuited for any actual heavy workloads as are any of their PC competitors.
That's the entire problem here: people are using the wrong kind of hardware for certain workloads, they are expecting to run every possible workload on certain hardware (no matter if Mac or PC) which is incorrect because you can't. iMacs aren't suited for all workloads and neither is the nMP or any other PC. When pushing any of such hardware you'll run it at the max and it will be noisy and hot. That's just physics. Another thing is definition: what you consider a heavy workload might be out of the ball park for someone else and a light workload for another. The fact that things like memory and cpu usage is at its max doesn't mean there is a heavy workload. There are quite a lot of workloads that simply use everything if possible. Whenever you run something else alongside it, it will return system resources. Take a look at how load of a machine is calculated in UNIX/Linux systems and you'll understand what I mean by this (which is not for the faint hearted btw!).
And btw, if you meant to compare it to a PC then don't compare it to an nMP at all. If you do a comparison between the iMac 5k and nMP or a PC you need to keep the specs the same. This also means that you need to use a 5K display for the nMP or PC setup. If not then you might as well compared it to a Raspberry Pi 2 since you are comparing apples and oranges anyway.
Shaun, I really have to ask if you are so enamored of your other computers, why the hell are you slumming over here in the iMac forum?
Let me get on with my professional, paid work on my crap 5K iMac and you can go back to the Mac Pro forum.
Every compute platform is a compromise, and iMacs are no exception. A big majority of Mac users was happy to ditch those big boxes that were hanging under our desks, for the convenience of having a computer that more or less disappeared into our display. I'm not saying everyone was happy, but most were OK with that compromise. The trade-off is that we have less air volume, and cooling is a bit of a challenge. Well, that along with upgrade-ability and some other things.
Anyhow, most users will only rarely run at max utilization. I'm not familiar with the app that OP was using, but I do have lots of time with Handbrake, and it has taxed all of my Macs beyond anything I've every used. It grabs every bit of resources available to it for as long as its queue tells it to. Unlike a creative professional who may be working on one movie, using apps like this is equivalent to throwing bunches of movie into the queue (I suspect I've had Handbrake queues with a couple dozen movies). While a common use case, it's nonetheless an extreme one. It's not the peaks and valleys of every day compute, but more akin to the sustained peak loads that something like SLURM will throw at an HPC cluster or Supercomputer. OK, maybe a bit like that, but fortunately only for shorter periods of time.
There are systems that are designed to live with sustained peak performance for years. They've got massive cooling systems, massive I/O, and are much more complex than their traditional enterprise brethren, again we call them HPC systems or Supercomputers. Look at the Top 500 list - Probably 490 of those systems are running 95% or higher, at this very moment. Take the kinds of workloads that they're designed to handle (100%+ sustained utilization 24/7/365) and throw it at the average Enterprise server, and it'll be toasted in days or weeks - because they're designed to visit peak performance, not to spend their lives there.
Guess what, your iMac was also designed to spend a bit of time with such workloads, but not live there. The nMP could probably spend a Hell of a lot more time there, maybe even living there with the right cooling and infrastructure around it. Those big goofy Gaming PCs with the massive chillers could also likely stay there a long time, though I'm still not sure if they could permanently live there? Point is, those massive ripping queues is perhaps the most taxing thing you'll ever throw at your system. Naturally, it's gunna' hem and haw a bit, while you're pushing it that hard.
But I threw rather lengthy queues at my iMacs for years, and they lived just fine to tell about it. But if I was routinely pushing that kind of load for more than an hour, I would question whether or not I bought an appropriate platform.
Meanwhile, placing a small fan near the back of your iMac to push that warm air our of the way will do wonders for cooling.
Anyhow, most users will only rarely run at max utilization. I'm not familiar with the app that OP was using, but I do have lots of time with Handbrake, and it has taxed all of my Macs beyond anything I've every used. It grabs every bit of resources available to it for as long as its queue tells it to. Unlike a creative professional who may be working on one movie, using apps like this is equivalent to throwing bunches of movie into the queue (I suspect I've had Handbrake queues with a couple dozen movies). While a common use case, it's nonetheless an extreme one. It's not the peaks and valleys of every day compute, but more akin to the sustained peak loads that something like SLURM will throw at an HPC cluster or Supercomputer. OK, maybe a bit like that, but fortunately only for shorter periods of time.
There are systems that are designed to live with sustained peak performance for years. They've got massive cooling systems, massive I/O, and are much more complex than their traditional enterprise brethren, again we call them HPC systems or Supercomputers. Look at the Top 500 list - Probably 490 of those systems are running 95% or higher, at this very moment. Take the kinds of workloads that they're designed to handle (100%+ sustained utilization 24/7/365) and throw it at the average Enterprise server, and it'll be toasted in days or weeks - because they're designed to visit peak performance, not to spend their lives there.
Guess what, your iMac was also designed to spend a bit of time with such workloads, but not live there. The nMP could probably spend a Hell of a lot more time there, maybe even living there with the right cooling and infrastructure around it. Those big goofy Gaming PCs with the massive chillers could also likely stay there a long time, though I'm still not sure if they could permanently live there? Point is, those massive ripping queues is perhaps the most taxing thing you'll ever throw at your system. Naturally, it's gunna' hem and haw a bit, while you're pushing it that hard.
But I threw rather lengthy queues at my iMacs for years, and they lived just fine to tell about it. But if I was routinely pushing that kind of load for more than an hour, I would question whether or not I bought an appropriate platform.
Meanwhile, placing a small fan near the back of your iMac to push that warm air our of the way will do wonders for cooling.
Every compute platform is a compromise, and iMacs are no exception. A big majority of Mac users was happy to ditch those big boxes that were hanging under our desks, for the convenience of having a computer that more or less disappeared into our display. I'm not saying everyone was happy, but most were OK with that compromise. The trade-off is that we have less air volume, and cooling is a bit of a challenge. Well, that along with upgrade-ability and some other things.
Anyhow, most users will only rarely run at max utilization. I'm not familiar with the app that OP was using, but I do have lots of time with Handbrake, and it has taxed all of my Macs beyond anything I've every used. It grabs every bit of resources available to it for as long as its queue tells it to. Unlike a creative professional who may be working on one movie, using apps like this is equivalent to throwing bunches of movie into the queue (I suspect I've had Handbrake queues with a couple dozen movies). While a common use case, it's nonetheless an extreme one. It's not the peaks and valleys of every day compute, but more akin to the sustained peak loads that something like SLURM will throw at an HPC cluster or Supercomputer. OK, maybe a bit like that, but fortunately only for shorter periods of time.
There are systems that are designed to live with sustained peak performance for years. They've got massive cooling systems, massive I/O, and are much more complex than their traditional enterprise brethren, again we call them HPC systems or Supercomputers. Look at the Top 500 list - Probably 490 of those systems are running 95% or higher, at this very moment. Take the kinds of workloads that they're designed to handle (95%+ sustained utilization 24/7/365) and throw it at the average Enterprise server, and it'll be toasted in days or weeks - because they're designed to visit peak performance, not to spend their lives there.
Guess what, your iMac was also designed to spend a bit of time with such workloads, but not live there. The nMP could probably spend a Hell of a lot more time there, maybe even living there with the right cooling and infrastructure around it. Those big goofy Gaming PCs with the massive chillers could also likely stay there a long time, though I'm still not sure if they could permanently live there? Point is, those massive ripping queues is perhaps the most taxing thing you'll ever throw at your system. Naturally, it's gunna' hem and haw a bit, while you're pushing it that hard.
But I threw rather lengthy queues at my iMacs for years, and they lived just fine to tell about it. But if I was routinely pushing that kind of load for more than an hour, I would question whether or not I bought an appropriate platform.
Meanwhile, placing a small fan near the back of your iMac to push that warm air our of the way will do wonders for cooling.
Anyhow, most users will only rarely run at max utilization. I'm not familiar with the app that OP was using, but I do have lots of time with Handbrake, and it has taxed all of my Macs beyond anything I've every used. It grabs every bit of resources available to it for as long as its queue tells it to. Unlike a creative professional who may be working on one movie, using apps like this is equivalent to throwing bunches of movie into the queue (I suspect I've had Handbrake queues with a couple dozen movies). While a common use case, it's nonetheless an extreme one. It's not the peaks and valleys of every day compute, but more akin to the sustained peak loads that something like SLURM will throw at an HPC cluster or Supercomputer. OK, maybe a bit like that, but fortunately only for shorter periods of time.
There are systems that are designed to live with sustained peak performance for years. They've got massive cooling systems, massive I/O, and are much more complex than their traditional enterprise brethren, again we call them HPC systems or Supercomputers. Look at the Top 500 list - Probably 490 of those systems are running 95% or higher, at this very moment. Take the kinds of workloads that they're designed to handle (95%+ sustained utilization 24/7/365) and throw it at the average Enterprise server, and it'll be toasted in days or weeks - because they're designed to visit peak performance, not to spend their lives there.
Guess what, your iMac was also designed to spend a bit of time with such workloads, but not live there. The nMP could probably spend a Hell of a lot more time there, maybe even living there with the right cooling and infrastructure around it. Those big goofy Gaming PCs with the massive chillers could also likely stay there a long time, though I'm still not sure if they could permanently live there? Point is, those massive ripping queues is perhaps the most taxing thing you'll ever throw at your system. Naturally, it's gunna' hem and haw a bit, while you're pushing it that hard.
But I threw rather lengthy queues at my iMacs for years, and they lived just fine to tell about it. But if I was routinely pushing that kind of load for more than an hour, I would question whether or not I bought an appropriate platform.
Meanwhile, placing a small fan near the back of your iMac to push that warm air our of the way will do wonders for cooling.
Indeed. I've seen more powerful computers do much worse just because of where they were placed. If the machine cannot properly vent its heat to its surroundings then it really doesn't matter how good or bad the cooling system of the machine is. Also, what we are seeing in datacentres with servers, switches, etc. is that these are actually quite able to sustain heat for long periods of time. There simply isn't a need to cool the entire room to 18C to get the machines to a case temp of 30C. If they run at 40C they're perfectly fine. The biggest advantage of all this is less energy wasted by cooling systems. Which also means cheaper hosting.
Your iMac will be ok. It's what apples obsession with thinness gets you. That's why throttling is a built in feature. Your cpu will run at 3.3ghz to keep itself from burning up. dGpus are much more fragile whilst I hardly ever hear of fried CPUs let alone a recall for them. I have a dedicated pc for gaming and handbrake type of rendering where it runs at 4.6ghz all day long at 65C with a noctua nh15 cooler that probably takes the same volume as the whole inside of the iMac case.
Throttling of the CPU is an Intel technology and throttling in the GPU is an AMD/Nvidia technology. It's not there because of Apple. Both Intel, AMD and Nvidia have had experiences with chips overheating and being burned. At first there were features on the motherboards that would shutdown a machine when it overheated, now it simply throttles back. However, both CPUs and GPUs have changed considerably over time. They've become more energy efficient and a side effect of that is that instead of running at their max capacity, they now run at their minimum capacity and scale up and down as necessary. It is more demand driven. When it comes to GPUs we still have a long way to go on the energy efficiency road though. These still are the hottest components in a machine (especially those from AMD and Nvidia).
One of the latest advances is from IBM where they are using a special cooling system that is part of the chip itself. It resembles the blood system used in some animals (they use it for cooling). This is require since chips are being build on smaller scales. Ordinary cooling systems become less efficient. They also want to have hardware run at a certain temperature because then it run the most efficient.
One of the latest advances is from IBM where they are using a special cooling system that is part of the chip itself. It resembles the blood system used in some animals (they use it for cooling). This is require since chips are being build on smaller scales. Ordinary cooling systems become less efficient. They also want to have hardware run at a certain temperature because then it run the most efficient.
Thanks
Once the new iMac comes I will keep you informed!
Of course I go first without external fan to see the difference.
Now, to find a suitable USB powered fan.
And I'll do my professional paid work on my nMP, game on my PC, neither of which overheat. And why am I on here? I'll leave you to guess...
Luckily the exchange to a new one was worth.
My final measurements have shown very clearly that the foregoing exemplary model, nevertheless had a problem around cooling.
As you saw in the 1st model at 100% CPU load, the Fanspeed (2850 RPM) runned continuously at its maximum.
In this 2nd model with a 100% CPU load, luckily the Fanspeed gets no higher than 2280 RPM. Also it strikes me at this 2nd model, that the cooling unit at 100% CPU load is now much less.
I can therefore say that there is enough reserve to cool the CPU and the noise level is also clearly calmer.
Finally I can enjoy this iMac i7 for its purpose, and I will not be stressed any more, because it is a much quieter running fan.
100% speedfan (bad cooling)
Speedfan (silent cooling with reserve)
My final measurements have shown very clearly that the foregoing exemplary model, nevertheless had a problem around cooling.
As you saw in the 1st model at 100% CPU load, the Fanspeed (2850 RPM) runned continuously at its maximum.
In this 2nd model with a 100% CPU load, luckily the Fanspeed gets no higher than 2280 RPM. Also it strikes me at this 2nd model, that the cooling unit at 100% CPU load is now much less.
I can therefore say that there is enough reserve to cool the CPU and the noise level is also clearly calmer.
Finally I can enjoy this iMac i7 for its purpose, and I will not be stressed any more, because it is a much quieter running fan.
100% speedfan (bad cooling)
Speedfan (silent cooling with reserve)
The fan speed on the iMac at the office seems to vary a lot during heavy load of the CPU. I've been running a couple of processes for the past few days that take up 100% CPU on a Core i5 of an iMac 2014 5k Retina. For the first five minutes or so the fan speed ramped up quite a bit (the peak appears small in the 7 days overview because of averaging), but then settled at low speed again. Over the course of the days it occasionally ramps up before settling again. It varies from barely audible to the occasional noticeable humming, but that's in a quiet office environment. All the time the CPU was running at 100%, CPU core temperatures varied between 85 to 95˚C, the CPU proximity remained stable at 66˚C.
I was quit surprised to see the fan speed drop even tough the temperature remained high. And no, there was no case of thermal throttling of the CPU. It actually ran at a stable 3.7GHz, slightly above the baseline performance of the CPU. Not sure why the fans go down after a while, but if you are experiencing a lot of fan noise, maybe give it a couple of minutes for the system to reach some equilibrium.
I was quit surprised to see the fan speed drop even tough the temperature remained high. And no, there was no case of thermal throttling of the CPU. It actually ran at a stable 3.7GHz, slightly above the baseline performance of the CPU. Not sure why the fans go down after a while, but if you are experiencing a lot of fan noise, maybe give it a couple of minutes for the system to reach some equilibrium.
Good job Apple even as we pay upwards of $4000 on these iMacs, their workers still can't apply $.03 of thermal paste correctly. Glad to see your 2nd machine is much better.Luckily the exchange to a new one was worth.
My final measurements have shown very clearly that the foregoing exemplary model, nevertheless had a problem around cooling.
As you saw in the 1st model at 100% CPU load, the Fanspeed (2850 RPM) runned continuously at its maximum.
In this 2nd model with a 100% CPU load, luckily the Fanspeed gets no higher than 2280 RPM. Also it strikes me at this 2nd model, that the cooling unit at 100% CPU load is now much less.
I can therefore say that there is enough reserve to cool the CPU and the noise level is also clearly calmer.
Finally I can enjoy this iMac i7 for its purpose, and I will not be stressed any more, because it is a much quieter running fan.
100% speedfan (bad cooling)
Speedfan (silent cooling with reserve)
Luckily the exchange to a new one was worth.
...
Finally I can enjoy this iMac i7 for its purpose, and I will not be stressed any more, because it is a much quieter running fan.
Awesome! I'm glad you got this sorted out with Apple despite many folks on this thread saying that was how it was supposed to work and that you shouldn't worry about it. Someone even suggested you shouldn't run the application that was causing the high temps and high fan speed!
You've also motivated me to look into TG Pro.
Thnx
Yes, after a few days.
Finally here an silent iMac where the cooling unit at 100% CPU load, has the necessary reserves to work full power.
If it can help you: my Late 2013 iMac (i7 3.5GHz) on heavy load:
And I don't like the GPU running at +100°C, because I've seen a lot of them burning to death... But I've never seen a modern CPU dying, by heat or something else: modern Intel CPU are rock solid and can stand 100°C without any damages. And they include a protection: if the temperature is close to the limit, they are shutting down themselves automatically before the damage
And I don't like the GPU running at +100°C, because I've seen a lot of them burning to death... But I've never seen a modern CPU dying, by heat or something else: modern Intel CPU are rock solid and can stand 100°C without any damages. And they include a protection: if the temperature is close to the limit, they are shutting down themselves automatically before the damage