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The new iMac is a lot noisier!
- Thread starter Darajavahus
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It is a quiet living room. From a foot and half away, I don't hear any noise from it under normal use. I don't have a hard drive in it.
Apple SSD use PCI-Express connection (on PC, SSD use only SATA connection) and so it seems to allow also 2 Gb/s speed during Write ! A new record.
On Read speeds, Apple Fusion drives included SSD are quite similar to those of these PCI-Express SSD, but Write speed is 3 times less...
So for example if you put your Lightroom catalog on the internal disk, Lightroom would potentially be able to write 3 times faster in it with an Apple SSD, than with the Fusion Drive, even when using the SSD part of the Fusion Drive (which is not potentially always the case, it could also use the hard drive part of the Fusion drive).
Explanation takes one word : overclocking
i5-7600K is just an overclocked verison of i5-7600 cpu.
And overclocking add heat (+20°C at full charge here it seems according to tomshardware tests yes)
saw some 7700k tests on youtube where temperature instantly goes from 30C to 100C and from 100C to 30C when benchmarking starts and finished. But physically cpu is cold so there is suggestion that temp sensors are defected or intel prevents from high OC to save future sales
Defective? No.
They are measuring core temps, not CPU package temps. CPU package temps are considerably cooler (although not specifically "cool").
The fact that the chips can jump up and down so quickly is a testament to their great design. And the fact that they will throttle as necessary is also a great design feature.
In 2017 it's harder to destroy a CPU by overclocking than it used to be, because the CPUs have self-protective mechanisms.
90-100C all day, 5 days a week, for years? What will you be doing?
Most of the time for me I'm in the 40-55C range. It idles at 39C.
From a thermal design POV there is nothing elegant or good about having a CPU that can go from 40degC to 100degC in a minute. Nothing. No gamer would build such a PC and as a long time high reliability EE design engineer - nothing above 25degC rise for components was tolerated. FWIW the thermal design is perfect for the i5 3.4 and 3.5, neither of these will ever exceed 70degC. The i7 will hit max and if left there will probably throttle as well. All that said Apple has been doing this for years with no massive failures for high end models - the 2013 MacPro and Mac Pros before - never worked like that though
.The iMac will be fine (if a bit noisy with the fan going full bore all the time). My advice - Apple care and sell it after 2.5 years - rinse and repeat
Interesting, but then again these chips are specifically built to operate safely up to 100C. The MacBooks are fanless after all for example. The chips throttle at 100C but they just keep on running. Actually I think for most of the laptop chips the safe operating temperature is actually up to 105C.From a thermal design POV there is nothing elegant or good about having a CPU that can go from 40degC to 100degC in a minute. Nothing. No gamer would build such a PC and as a long time high reliability EE design engineer - nothing above 25degC rise for components was tolerated. FWIW the thermal design is perfect for the i5 3.4 and 3.5, neither of these will ever exceed 70degC. The i7 will hit max and if left there will probably throttle as well. All that said Apple has been doing this for years with no massive failures for high end models - the 2013 MacPro and Mac Pros before - never worked like that though
The iMac will be fine (if a bit noisy with the fan going full bore all the time). My advice - Apple care and sell it after 2.5 years - rinse and repeat
As you know, fan starts ramping up before it hits 100C though.
Just out of curiosity I installed SMc Fan control to turn up the fan and see what the big deal was, and yeah, it's damn loud lol. In the base model I got, I transcoded a 4K video for 4 hours that had all cores running maxed and the fan didn't even budge from 1200RPM.
I can't imagine haven't it get that loud during use though, it would be hella annoying
I can't imagine haven't it get that loud during use though, it would be hella annoying
Yeah, but your 3.4 GHz model couldn't keep up with your Plex transcoding. You were getting stuttering in the video stream, because the computer wasn't fast enough.
So, in this scenario (3.4 GHz i5-7500), the computer can't do the task but is quiet.
In the other scenario (4.2 GHz i7-7700K), the computer may be able the accomplish the task, but is loud.
Either way, you're screwed.
Honestly, I think you should rethink your use of the iMac for Plex transcoding of 4K HEVC material, because you're probably not going to be satisfied either way.
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However, your post does give me pause. If the 7500 truly is completely silent at 100% load, I may have to consider that. I still have a week to return this.
I'd consider getting the 7600 with 575. Like I said, for 98% of what I do, the fan is silent. However, for the occasions I have to sit at my desk and convert a video at the same time, the fan would be annoying.
Has anyone tested the 7600 at full tilt CPU (not GPU) (eg. transcoding video) for say 10 minutes? Does the fan ramp up?
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Yeah, but your 3.4 GHz model couldn't keep up with your Plex transcoding. You were getting stuttering in the video stream, because the computer wasn't fast enough.
So, in this scenario (3.4 GHz i5-7500), the computer can't do the task but is quiet.
In the other scenario (4.2 GHz i7-7700K), the computer may be able the accomplish the task, but is loud.
Either way, you're screwed.
Honestly, I think you should rethink your use of the iMac for Plex transcoding of 4K HEVC material, because you're probably not going to be satisfied either way.
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However, your post does give me pause. If the 7500 truly is completely silent at 100% load, I may have to consider that. I still have a week to return this.
I'd consider getting the 7600 with 575. Like I said, for 98% of what I do, the fan is silent. However, for the occasions I have to sit at my desk and convert a video at the same time, the fan would be annoying.
Has anyone tested the 7600 at full tilt CPU (not GPU) (eg. transcoding video) for say 10 minutes? Does the fan ramp up?
Lol touché!
As for the 4K HEVC material, I'm exploring options. My KS8000 can accept the videos and plays it directly so no hit on iMac so I have some tweaking in how I'm going to approach using it. But my 2011 iMac is going to a new home, and this 27" ain't going anywhere.
Well, as previously posted, I'm having second thoughts. I'm trying to decide whether or not I want perfect silence or 30%+ more video conversion speed.
One thing I noticed though while playing around in the store is that applications like Photos are quite responsive even on the MacBook Pros. The key differentiator in most actions is not the CPU, but in fact the storage. The SSDs were very fast, but platter drives were noticeably slower. This may partially be due to the fact that the Apple Store Fusion drives are really just platter drives without the Fusion part in many instances, but in this case it would matter, because if you have several hundred GB of photos, you won't be on the SSD part of the Fusion drive anyway. You'll be getting your data off the platter drive, which is the limiting factor.
OTOH, transcoding on the 7700K makes for fan noise. I don't do this often, but if I have to do it while sitting at the desk, it could get annoying. And if don't do this often, perhaps having the slower machine isn't such a bad thing, as long as everything else is the same. I'd lean toward the 7600 though, not the 7500, unless someone tells me the 7600 ramps up the fan after 10 minutes of video encoding (probably not if the 7500 doesn't). And if it does ramp up on the 7600, I suppose I could just turn off Turbo Boost, to make it even slower than a 7500.
I'd be interested in this too. However, Tom's Hardware did some testing of the 7600 vs the 7600K and with a pegged CPU, the 7600 was cooler, although the 7600K wasn't bad.
The 7700K was way hotter though.
I mentioned Tom's test above, but AnandTech put the 7600K as near the 7600 in terms of power consumption. I suspect there is variability, but given the TDP it's probably more likely the 7600 would on average be significantly cooler.
I think the way to reign in the heat of the 7600K though would be to turn off Turbo Boost.
7700K: 4.2 and 4.5/4.4/4.4
7600K: 3.8 and 4.2/4.1/4.0
7600: 3.5 and 4.1/4.0/3.9
7500: 3.4 and 3.8/3.7/3.6
The key here is that for heavily threaded applications, the 7600 is nearly identical to the 7600K.
Cinebench:
7700K: 995
7600K: 688
7600: 666
7500: 617
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Well I can tell you that I was sitting at my desk playing around with the new toy encoding with handbrake, browsing, setting it all up, didn't have any hiccups even though handbrake was eating up all my CPU resources, and even after an hour straight that fan never left 1200 rpm, that is until I installed SMC and turned it up lol.
Overall this rig with do me just fine. If I have to do audio encoding on some 4K files because my tv doesn't support it, then meh. But I can do it in peace and quiet and hope that Xbox One X can natively handle these files through Plex.
Overall this rig with do me just fine. If I have to do audio encoding on some 4K files because my tv doesn't support it, then meh. But I can do it in peace and quiet and hope that Xbox One X can natively handle these files through Plex.
The imac series has one cooling system. The i5 3.4 at 100% CPU is 66degC in the test I did. Neither the smidge faster 3.5 or the 575 look at all worth it for me. 3% points at best. In my perpetual flip flop I have put the i7 aside (return too Apple this week) and will use only the i5 base till Sunday (assuming all goes well). Although I am still mostly a real time audio guy my sessions are just not very big and I don't see that changing for the next year. If the i5/3.4/512G SSD will work it will save me $1K (almost 1/3 of the cost). If a year from now the machine is holding me back I will have two more worthy possibilities to choose from - iMac Pro and Mac Pro. Both will feature much better cooling systems for higher core CPUs. Assuming i5 does well I will order the BTO 512SSD version (though I surprisingly don't hate the Fusion performance)... LOL
PS (IMO) - these CPUs are not built to run at 100degC they just can run there. Regardless - absolute temperature is not the failure mechanism I would worry about with these. Thermal cycling is the big bad boy (and a key to all MilSpec and Space grade testing - my old line of work). The CPU is attached to solder pads to get signals in and out as well as to the heatsink path. These joints always have a temperature coeffient mismatch that causes mechanical stress as temperature goes up and down. The large the Delta T, the larger the stress. Worse stress if this happens quickly too. The though of this happening 100s of times every day I use the computer is just more than this engineer can bear... Hence I think it is either the i5 7500 for me or I will keep my Mac Pro 2013 going (but it would be much better to sell long before the new one comes out!).
PS (IMO) - these CPUs are not built to run at 100degC they just can run there. Regardless - absolute temperature is not the failure mechanism I would worry about with these. Thermal cycling is the big bad boy (and a key to all MilSpec and Space grade testing - my old line of work). The CPU is attached to solder pads to get signals in and out as well as to the heatsink path. These joints always have a temperature coeffient mismatch that causes mechanical stress as temperature goes up and down. The large the Delta T, the larger the stress. Worse stress if this happens quickly too. The though of this happening 100s of times every day I use the computer is just more than this engineer can bear
... Hence I think it is either the i5 7500 for me or I will keep my Mac Pro 2013 going (but it would be much better to sell long before the new one comes out!).The imac series has one cooling system. The i5 3.4 at 100% CPU is 66degC in the test I did. Neither the smidge faster 3.5 or the 575 look at all worth it for me. 3% points at best. In my perpetual flip flop I have put the i7 aside (return too Apple this week) and will use only the i5 base till Sunday (assuming all goes well). Although I am still mostly a real time audio guy my sessions are just not very big and I don't see that changing for the next year. If the i5/3.4/512G SSD will work it will save me $1K (almost 1/3 of the cost). If a year from now the machine is holding me back I will have two more worthy possibilities to choose from - iMac Pro and Mac Pro. Both will feature much better cooling systems for higher core CPUs. Assuming i5 does well I will order the BTO 512SSD version (though I surprisingly don't hate the Fusion performance)... LOL
PS (IMO) - these CPUs are not built to run at 100degC they just can run there. Regardless - absolute temperature is not the failure mechanism I would worry about with these. Thermal cycling is the big bad boy (and a key to all MilSpec and Space grade testing - my old line of work). The CPU is attached to solder pads to get signals in and out as well as to the heatsink path. These joints always have a temperature coeffient mismatch that causes mechanical stress as temperature goes up and down. The large the Delta T, the larger the stress. Worse stress if this happens quickly too. The though of this happening 100s of times every day I use the computer is just more than this engineer can bear
Thanks for sharing your insights on how the thermal cycling can affect the longevity of the component. Helps a lot in making my decision.
The imac series has one cooling system. The i5 3.4 at 100% CPU is 66degC in the test I did. Neither the smidge faster 3.5 or the 575 look at all worth it for me. 3% points at best. In my perpetual flip flop I have put the i7 aside (return too Apple this week) and will use only the i5 base till Sunday (assuming all goes well). Although I am still mostly a real time audio guy my sessions are just not very big and I don't see that changing for the next year. If the i5/3.4/512G SSD will work it will save me $1K (almost 1/3 of the cost). If a year from now the machine is holding me back I will have two more worthy possibilities to choose from - iMac Pro and Mac Pro. Both will feature much better cooling systems for higher core CPUs. Assuming i5 does well I will order the BTO 512SSD version (though I surprisingly don't hate the Fusion performance)... LOL
PS (IMO) - these CPUs are not built to run at 100degC they just can run there. Regardless - absolute temperature is not the failure mechanism I would worry about with these. Thermal cycling is the big bad boy (and a key to all MilSpec and Space grade testing - my old line of work). The CPU is attached to solder pads to get signals in and out as well as to the heatsink path. These joints always have a temperature coeffient mismatch that causes mechanical stress as temperature goes up and down. The large the Delta T, the larger the stress. Worse stress if this happens quickly too. The though of this happening 100s of times every day I use the computer is just more than this engineer can bear
I agree with your points. The i5/570 configuration is great for the iMac 5K; perhaps get the i5/575 if you really want to squeeze more power out of the machine while staying silent and cool.
Beyond the i5/575 configuration, though, I'd look at the iMac Pro launching in 5 months or the Mac Pro that is launching next year, instead.
A very good explaination.The imac series has one cooling system. The i5 3.4 at 100% CPU is 66degC in the test I did. Neither the smidge faster 3.5 or the 575 look at all worth it for me. 3% points at best. In my perpetual flip flop I have put the i7 aside (return too Apple this week) and will use only the i5 base till Sunday (assuming all goes well). Although I am still mostly a real time audio guy my sessions are just not very big and I don't see that changing for the next year. If the i5/3.4/512G SSD will work it will save me $1K (almost 1/3 of the cost). If a year from now the machine is holding me back I will have two more worthy possibilities to choose from - iMac Pro and Mac Pro. Both will feature much better cooling systems for higher core CPUs. Assuming i5 does well I will order the BTO 512SSD version (though I surprisingly don't hate the Fusion performance)... LOL
PS (IMO) - these CPUs are not built to run at 100degC they just can run there. Regardless - absolute temperature is not the failure mechanism I would worry about with these. Thermal cycling is the big bad boy (and a key to all MilSpec and Space grade testing - my old line of work). The CPU is attached to solder pads to get signals in and out as well as to the heatsink path. These joints always have a temperature coeffient mismatch that causes mechanical stress as temperature goes up and down. The large the Delta T, the larger the stress. Worse stress if this happens quickly too. The though of this happening 100s of times every day I use the computer is just more than this engineer can bear
I mean the iMac is an AIO. It is designed for those who dont want to build their computer from scratch and once you buy it, either use it or forget it. The space in this machine is limited, it doesnt meant to provide the horse power which should be rather provided by a mac pro. Recently people is buying iMac For a mac pro purpose is just because the current mac pro is a ****. There is no alternative for them until Apple start putting the high end cpus in iMac, so they turn their head there. Apple is tricky here because they know the same yet they still offer you 7700k in iMac regardless the cooling system is efficient enough.
If Apple had offered the i7-7700 (65W) instead of the i5-7600K with the Radeon Pro 580, the configuration would be a lot more popular. There are a lot of creative professionals who would love to have the best GPU available with a cooler i7 like the 7700.
I'm not sure why Apple decided to offer the i7-7700 for the 21.5 inch but not for the 27 inch.