Question: Buying iMac 2017 27# 5K? - Fan noise - Read this!
(Config: 4,2 GHz Intel Core i7, 40 GB 2400 MHz DDR4, Macintosh HD 1TB (SSD), Radeon Pro 580 8 GB)
If the CPU load reaches about 35% (for instance playing a Flash game) the fan will start blowing at about 50% of its maximum speed, which is annoying. This is my second 2017 Mac and they react similar. If the CPU reaches a load of 50% or more and a temperature of the CPU can go up to a whopping 95 degrees celsius the fan will blow at 100% and your wondering who is vacuuming your room?
So, if your into Zen like Steve Jobs, maybe you should not buy the new 2017 iMac. This is not what I expected from Apple.
iMac (Retina 5K, 27-inch, 2017), macOS High Sierra (10.13.2), 4,2 GHz Intel Core i7