user1234
macrumors 6502a
The scaling applies to the UI and anything not optimized for retina, but high res media will be showed at native resolution. Otherwise having 5k res would be pointless
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The new iMac is a lot noisier!
- Thread starter Darajavahus
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The scaling applies to the UI and anything not optimized for retina, but high res media will be showed at native resolution. Otherwise having 5k res would be pointless
I got my 27" 4.2GHz i7 yesterday - it's beautiful - but I am concerned about the temps I'm seeing.
First order of business, straight out of the box, was to install iStat Menus and run Geekbench and Cinebench. I'll report on my numbers later but get this:
The benchmarks pushed the temps up to high 90'sC. Only during Cinebench did the fans kick on (peaking briefly at 2600rpm) but generally stayed at 1200rpm. Temps peaked at 116C and hovered around 100C for the rest of the evening, even when I was barely doing anything. I didn't want to fry my brand new system so I spent the rest of the night doing other set-up and copying files but nothing too intensive. Still stayed around 100C with fans at a calm, silent 1200rpm. Room temp is a normal 23C.
I know the fan is working but damn, that just seems too hot! From reports I read here, I thought the fan would be kicking in MORE than less. I'll be installing more RAM soon, doing more observations and final benchmarks, and report back.
Anyone else seeing temps hovering at 100C? Any chance iStat Menus is wildly inaccurate? (I only recently tried it and plan to register - great program)
First order of business, straight out of the box, was to install iStat Menus and run Geekbench and Cinebench. I'll report on my numbers later but get this:
The benchmarks pushed the temps up to high 90'sC. Only during Cinebench did the fans kick on (peaking briefly at 2600rpm) but generally stayed at 1200rpm. Temps peaked at 116C and hovered around 100C for the rest of the evening, even when I was barely doing anything. I didn't want to fry my brand new system so I spent the rest of the night doing other set-up and copying files but nothing too intensive. Still stayed around 100C with fans at a calm, silent 1200rpm. Room temp is a normal 23C.
I know the fan is working but damn, that just seems too hot! From reports I read here, I thought the fan would be kicking in MORE than less. I'll be installing more RAM soon, doing more observations and final benchmarks, and report back.
Anyone else seeing temps hovering at 100C? Any chance iStat Menus is wildly inaccurate? (I only recently tried it and plan to register - great program)
EugW
macrumors P6
That does not seem right. Either you’re measuring something else or iStat Menus is reporting incorrect numbers, because it seems the fan is working as it should otherwise.
Try installing the Intel Power Gadget application. It includes temp monitoring.
https://software.intel.com/en-us/articles/intel-power-gadget-20
Edit: See post below.
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EugW
macrumors P6
That would explain it. However, for me it defaulted to Celsius. Maybe because I live in Canada? Or maybe it was an old preference setting still on the drive.
100F is 38C, which is a normal idle temp.
/facepalm if that's all it is. I've been so used to reading and dealing in Celsius that I honestly didn't even check that it could report in F.
EDIT: I was mistaken - iStat Menus defaulted to F and since it doesn't show units I assumed C. Temps are fine! It's running at a nice 39C right now while I browse the forums.
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fokmik
Suspended
i hope apple will go for the normal imacs in 2018 with same internal thermal like the imac pro, with 2 fans...i think 2 fans at 1200rpm are probably a little bit noisier than current one, but they will keep the temp at max 80 in any config and never go more than 2000 rpm and this mean a more quiet device device, i5 i7 and any dGPU+i wont those internal speakers from imac pro...they really are outstanding for an all in one
I was actually very surprised by the iMac speakers. I have a speaker set and sub that was like $80 from Walmart and they still have better sound, but if I hadn't gotten those free from a friend, iMac speaker would be fine for casual use. I wish they hadn't tucked the fan vent in behind the stand tho. Feels like the hot air comes out, hits the stand, and just circulates around the iMac base. Instead of going out and up away from the Mac. It's stupid
EugW
macrumors P6
In my 2017 27”, the hot air vents out near the top, on the back. However, that model is a different shape. It does not taper at the sides and top like the 2017.
Jack Burton
macrumors 6502a
This is extremely good for me to read right now. So cinebencg R15 was hitting 39C during full multicore load? I kept seeing all of these temp doom and gloom posts on heat and noise.
I've been reading a lot on overclocking the new intel skyline-x chips. 39C in a thin iMac enclosure seems downright frozen by comparison!
EugW
macrumors P6
Jack Burton
macrumors 6502a
So his peak of 119 F during cinebench translates to 48.3C. Still not too bad, right? Noise is subjective (I'm sitting next to a giant AC vent, so I can't hear my own Mac fan noise), so that sounds decent to me.
Mine peaked at 116F (~47C) during Cinebench. Not bad at all! I spent way too much time reading about heat/temps on the forums (particularly this whole thread about the older iMacs) and never thought to check the temperature units in iStat Menus! Pretty stupid of me, I'll admit, but I was brand new to iStat and all the screenshots I'd seen were in Celsius. That first night I got the machine, I thought I had one that just ran super hot (100C) for no reason and was even starting to think about having to send it back.
I ran Prime95 benchmark last night and temps got up to about 47C again and the fans maxxed out, but it came right back down after the test was over. I wouldn't even say the fans are "noisy" at max rpm - they ARE audible, and I would say it's even a rather pleasant, calming sound (compared to other fans on other machines and game consoles).
I plan to post further benchmarks on my machine soon, but now that I know it's running fine, I can safely say the 2017 is truly one of the best computers ever made! A beautiful feat of engineering, design and artistry 🙂
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EugW
macrumors P6
Again, I think something is off there. Are you measuring the right thing, specifically the CPU cores? There are different CPU temps that can be measured.
With Handbrake encoding, I could get my 7700K to 100C. Furthermore, at 47C, the fan should never come on at all.
I am going from memory on my Prime95 benchmark test last night and am likely wrong on the temp (47C is low for max fan now that you mention it). I'll double-check when I get home.
Jack Burton
macrumors 6502a
joema2
macrumors 68000
That is a good point. The previous numbers I reported were from iStat Menus' default CPU temp which is "CPU proximity". I should have reported "CPU core" which was about 95-100C.
There is a big difference in how software uses the CPU when performing the same task. I transcoded a 44 second 100 mbps H264 4k file from a Sony A7RII to a 20 megabit/sec 4k H264 output file using single pass encoding. I got the following transcode performance on different machines and software. In the Handbrake cases the CPU core temp was about 95-100C. When transcoding with FCPX it was considerably lower -- about 80C -- even if I kept adding timeline length to increase the export time.
It's obvious from watching the CPU graphs that Apple is doing something different -- they are about 50%. They are probably using Quick Sync which off-loads the CPU by moving part of the transcoding task to hardware.
2015 iMac 27 i7, Handbrake 1.0.7: 1 min 53 sec
2017 iMac 27 i7, Handbrake 1.0.7: 1 min 40 sec
2015 iMac 27 i7, FCPX 10.3.4: 35.6 seconds
2017 iMac 27 i7, FCPX 10.3.4: 28.5 seconds
For a different transcode path where I imported the same H264 4k source material but transcoded it to ProRes proxy, the CPU numbers were higher. I suspect this is because FCPX could only use Quick Sync for the decode phase but the encode phase to ProRes was software only, since Quick Sync won't do that codec.
Jack Burton
macrumors 6502a
One thing I would like to note is that despite the high temps, it's hard to come across users who had problems with it in the long run. The 2014 model had a lot of throttling issues and there's still no reports of failing iMacs due to fried CPUs.
Few things in life are genuine needs. Air, water, food, shelter ... sure, those count.
Maybe a silent computer is just a want, but it feels like a need to me, at least. So much so that my other two computers reside in a separate room, tethered to monitors in my office.
To my ears, even the base iMac is too noisy, though I tolerate it. I bought it for its beautiful monitor, and to play with until a "real" Mac Pro is finally available again (which will go in that separate room).
I think Apple should develop a silent computer again, e.g. a silent version of the iMac. I don't care if it's less powerful, even. Oh, and please throw in an OLED display. Thanks in advance! 🙂
EugW
macrumors P6
Agreed PhD, can't wait to what the next few years will bring with the iMac. It's only going to get better (OLED, SSD standard, etc)
To correct my earlier post, my Prime95 test reached 55C for CPU Proximity, the default in iStat Menus. CPU Cores went to (at least) ~92C. I'll attach a screenshot I took around the peak of heat, but it was more or less an off-hand test.
My RAM arrives tomorrow and I'll have more time this weekend to really put the iMac through testing in it's final (for a long while at least) configuration with better notes and screenshots.
To correct my earlier post, my Prime95 test reached 55C for CPU Proximity, the default in iStat Menus. CPU Cores went to (at least) ~92C. I'll attach a screenshot I took around the peak of heat, but it was more or less an off-hand test.
My RAM arrives tomorrow and I'll have more time this weekend to really put the iMac through testing in it's final (for a long while at least) configuration with better notes and screenshots.
Attachments
EugW
macrumors P6
Yes, that sounds about right. As mentioned, with Handbrake h.265 encoding, It'd very quickly hit 91-100C with the 7700K, and the fan would be pegged at max.
In contrast, the i5-7600 under a similar load would be in the mid 70s after 5 minutes, and 83C after 10 minutes. Furthermore, even after 10 minutes, the fan never went past 1200 rpm (with minor fluctuations in the reading between approximately 1190 and 1210 rpm). It seems the temp usually has to go above 90C to get the fan going.
I was never once concerned the i7 would blow itself up though. I was just a bit annoyed by the fan noise.
Proximity is more meaningful for MacBooks. On iMacs, at least this generation, the individual CPU cores heat up much faster while the proximity sensor doesn't pick up the trend close enough. The fans on the other hand are reacting directly to core heat. I used to leave the proximity temp as the menu bar icon for iStat Menus on MBPs and Minis, but for this iMac I am using the fan RPM instead, which is a more useful indicator of heat activity and it takes less space than listing 4 double-digit temp in degrees. (I wish iStat has an item for average core temp).