There's nothing to fix. It's normal for a Mac to get hotter during intensive workloads. If you're not already doing so, use iStat Pro (free) or iStat Menus ($16) to get accurate readings of your temps, fan speeds, etc., rather than relying on your sense of touch or sound. A forum member has posted a copy of iStat Pro that has been "tweaked" to enhance compatibility with recent OS X versions. You can download it here.The new iMac retina, maxed out, will make a lot of noise and heat even watching a simple movie in fullscreen
All the fans will turn on, cant imagine doing more intesive gpu things
Hope this get fixed somehow....
There's nothing to fix. It's normal for a Mac to get hotter during intensive workloads.
Yes it's normal for it to get hotter during intensive load. But it's not normal for the iMac to get THAT hot. The 295x and 4GHz i7 will both throttle under heavy load and the fan will blast away at the highest speed. This indicates that the iMac clearly isn't built for components that powerful.
Now do the same with a 2013 i5 iMac. Yes the fans will speed up a little but not all the way, and it will not start throttling down the processors. That's how the iMac was designed to work.
The fully loaded RiMac has components in it that it clearly wasn't designed for. The cooling system is not adequete for it.
Will it hold up? Who knows? We'll see in a couple of years.
Your description of the iMac cooling system is outdated by the way. Time to do some catching up.
The reason for the M295X rating up the fans is its thermal envelope. The standard GPU, the M290X has a TDP of 100W, whereas the M295X has a TDP of a whopping 250W!
False. First, you claim it's not normal for the iMac to get THAT hot, but you have no idea what temps are involved, because the OP didn't specify. Second, you have no idea whether the fans spinned up because of increased load on the GPU or the CPU, or even specifically which processes were putting the workload on the system. You don't know if temps were anywhere near the throttling range and you don't know if the fans were spinning at full speed. Your assumption that the iMac isn't built for the components inside is evidence of your lack of understanding.Yes it's normal for it to get hotter during intensive load. But it's not normal for the iMac to get THAT hot. The 295x and 4GHz i7 will both throttle under heavy load and the fan will blast away at the highest speed. This indicates that the iMac clearly isn't built for components that powerful.
http://gpuboss.com/gpus/Radeon-R9-M295X-vs-Radeon-R9-M290X
If it's not the M295X, it's a specialized version of the M295X then?
The fact the fans spins up means it's clearly designed to deal with the heat.
Your assumption that the iMac isn't built for the components inside is evidence of your lack of understanding.
Yes, it does. If the fans were not able to keep the heat within the safe operating range, your Mac would automatically shut down.No it doesn't. It just means that the fans spin up in order to deal with the heat. It doesn't mean that it's doing an adequate job at cooling it down.
You have no evidence that it's throttling. Fans spinning faster is not evidence of throttling. They spin faster to avoid it. Apple obviously knows much more than you do about what is required to handle the heat generated by the iMac components. Just because you put a heavy workload on it and the fans spin up does not mean it's not functioning well, as designed.Having now had first hand experience with the fully loaded RiMac has confirmed my assumptions that the iMac isn't built to handle the heat of the 4GHz i7 and the 295x.
Put heavy load on either one of them, the fan will start blasting at full speed and the processor start to throttle.
It is so very clear that the cooling system of the iMac (which is amazing by the way) doesn't do an adequate job at cooling these components. If it did it would not start throttling so early on.
Yes, it does. If the fans were not able to keep the heat within the safe operating range, your Mac would automatically shut down.
You have no evidence that it's throttling. Fans spinning faster is not evidence of throttling. They spin faster to avoid it. Apple obviously knows much more than you do about what is required to handle the heat generated by the iMac components. Just because you put a heavy workload on it and the fans spin up does not mean it's not functioning well, as designed.
I did the testing to show the throttling with the i7. Is the result you're talking about a Handbrake test as well? Are there any comparisons that show time difference between the i5 and i7 running Handbrake? Does the i5 throttle at all? Can you point me to such a test? Thanks.The i7 spikes quickly to 100C on sustained load (a Handbrake job) and throttles at 3.8 GHz. It's well known that Haswell CPUs will do that as automatic thermal protection. There's nothing mysterious about this, notebooks do it all the time.
The fact that the i5 peaks out at 86C under the same load (and somewhat less throughput due to lack of HT) without bumping the fan past its default of 1200 RPM is a useful distinction.
Mixed in with a lot of hysterical speculation, there's been some measurement and analysis of throttling in this forum....
The problem is there's been a lot more of the former than the latter.
Professional testing has given a more balanced perspective. Under high simultaneous CPU & GPU stress, Mac Performance Guide described the fan noise as "reasonable and tolerable": http://macperformanceguide.com/iMac5K_2014-stress.html
In each of the below tests the 4Ghz retina iMac with M295X was faster than an 8-core new Mac Pro with dual D700s:
http://macperformanceguide.com/iMac5K_2014-createImageSeries.html
http://macperformanceguide.com/iMac5K_2014-CaptureOnePro-raw-to-JPEG.html
http://macperformanceguide.com/iMac5K_2014-UnigineValley.html
http://macperformanceguide.com/iMac5K_2014-Cinebench.html
http://macperformanceguide.com/iMac5K_2014-video-transcode4K.html
Professional testing has given a more balanced perspective. Under high simultaneous CPU & GPU stress, Mac Performance Guide described the fan noise as "reasonable and tolerable"
Why is no rpm value stated?"Reasonable and tolerable" is so very subjective. Why is no rpm value stated?
This is however not the result I got when I pushed the i7. The fan was blasting at full speed and not at all reasonable and tolerable by my measures.
Why is no rpm value stated?
Although I'm starting to think these Unigine Valley numbers should come with a little bit of an asterisk, I mean, how useful is a benchmark that rates the M290X, the M295X, and dual D700s with approximately the same FPS?
While that's high, it's not full speed, as others have reported 2700+ rpm under heavy load. Have you checked your specific temps?2600+ rpm
(most of the time between 2610-2643)
Try this: go here and download the HD .MP4 (1280x710) version of the video. Then do a conversion using the AppleTV 2 preset. You might want to also run it using the AppleTV 3 preset if you want a longer run. I'd appreciate if you could do this before tomorrow.For relative speed I've found the Geekbench multithreaded score to be pretty good guide, but I'm up for a throughput test if we can arrange it. Do you know of some substantial downloadable content that we could use for a 10 minute encode test?
The problem is there's been a lot more of the former than the latter.
Professional testing has given a more balanced perspective. Under high simultaneous CPU & GPU stress, Mac Performance Guide described the fan noise as "reasonable and tolerable": http://macperformanceguide.com/iMac5K_2014-stress.html
In each of the below tests the 4Ghz retina iMac with M295X was faster than an 8-core new Mac Pro with dual D700s:
http://macperformanceguide.com/iMac5K_2014-createImageSeries.html
http://macperformanceguide.com/iMac5K_2014-CaptureOnePro-raw-to-JPEG.html
http://macperformanceguide.com/iMac5K_2014-UnigineValley.html
http://macperformanceguide.com/iMac5K_2014-Cinebench.html
http://macperformanceguide.com/iMac5K_2014-video-transcode4K.html