Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.


Question: cpu temperature of iMac mid 2017 core 17

Hi all,

Since about a month I'm working with my new iMac which has these specs:

iMac Retina 5K, 27-inch, 2017

APPLE SSD SM0512L 512GB with APFS filesystem

Processor - 4,2 GHz Intel Core i7

RAM - 40 GB 2400 MHz DDR4

Radeon Pro 580 8 GB

I mainly use the Mac to edit the photographs I take. The first application in my workflow is Photoshop CC 2018 which never forces the CPU to very high temperatures. Depending on the size and number of layers the next applications in my workflow (ON1 Photo Raw 2018 or DXO Photolab), are regularly forcing the CPU temperature up top to 99ºC for the hottest core. Also file operations in Adobe Bridge and ON1 Photo RAW, like indexing, copying or moving, make the CPU temp going up neat to 99º C

But most of my photographs are 360º panoramic images which I stitch and edit on the mac. After this editing I process them to interactive panorama photographs to put on one of my websites. The stitching and viewer applications (Panoramastudio 3 Pro and PTGui) don't cause any serious problems. My panoramas can be up to 5 GB in size (and about 85000 x 5000 pixels) before I flatten all layers and although my mac is very powerful the CPU temp is constantly just below 100ºC while editing in ON1 Photo Raw 2018, DXO Photolab or Luminar. I'm worried about this issue because I never experienced this behaviour before with my previous mac with Core i5 3.4 GHz. So I'm wondering if some of you can tell me more about the "normal" temperature behaviour of the iMac and if these high temperatures are normal?


Mathieu Elissen

Posted on


Page content loaded

Nov 11, 2017 11:33 AM in response to Tjeuke In response to Tjeuke

Use Activity Monitor to Kill Runaway Processes

Use Activity Monitor on your Mac

Runaway applications can shorten battery runtime, affect performance, and increase heat and fan activity.

Should the above not prove helpful, then make an appointment at the Apple Genius Bar for service. If you need to find an Apple Store - Find a Store - Apple.

Nov 11, 2017 11:33 AM

Reply Helpful (1)

Nov 12, 2017 2:01 PM in response to Tjeuke In response to Tjeuke

Hi Kappy,

Activity Monitor is the most frequently used app on my Mac because of these thermal problems.

Already did the checks you mention, no runaway apps found, removed external equipment that surrounded the Mac to give it enough air to breath. I 'm going to visit my Apple dealer for a consult. Thanks for your help.


Nov 12, 2017 2:01 PM

Reply Helpful
User profile for user: Tjeuke

Question: cpu temperature of iMac mid 2017 core 17