iMac 5k i7 cpu hits 100 °C regularly
I recently bought the 5k 27" i7 iMac. When the cpu is idle it stays in the low 30s, when under moderate load (HD movies, internet, Photoshop etc) it doesn't really get over 50 °C, but when I use it to render stills/animations in Cinema 4D (or After Effects) and all 8 threads are being utilized the temperature stays almost constantly at 95 °C and regularly peaks at 100 °C! At this point the fan is louder than my vacuum cleaner, the frequency drops but the temperature never does. I did a test render for about an hour and the fan never managed to cool down the cpu under 90 °C, even if the frequency dropped from 4 GHz to about 3.8. I used Macs Fan Control and Intel's Power Gadget to monitor what is going on and got the same readings.
I don't think there is anything wrong with the cpu as it cools down to 45 °C in a matter of seconds after I stop rendering. The fault is (I guess) in the iMac's cooling system, since it uses the same heat sink for both the cpu and gpu (which by the way also gets over 90 °C after a few minutes of doing virtually nothing in Civilization V), and has to cool them both down, and the power supply, and the rest of the components all squeezed in a space smaller than some laptops have with only one fan.
My question is: how worried should I be? I don't think it is either normal or acceptable for the cpu to be at such high temperatures for longer periods of time. I don't do rendering every day, but I will do at least full 48 hours of rendering per month and having the cpu hitting the 100 °C mark every few seconds really doesn't sound right to me. Or am I just over reacting and it is perfectly normal for the i7 to operate in the 90+ range all the time?
iMac with Retina 5K display, OS X El Capitan (10.11.4)
