I have my MacBook Pro (Retina, 15-inch, Late 2013), 2.3GHz, i7, 16GB DDR3 Ram with macOS High Sierra version 10.13.3 connected to dual monitors LG. My laptop is connected to the charger, so I can close the lid and use just the 2 external monitors.
My issue comes gradually every time. First 20-30 min of usage seem normal, it works fine. After that the CPU goes crazy for some reason. The Activity Monitor shows kernal_task at over 500% CPU usage all the time. Which is not normal at all.
I don't know what's wrong or how to solve this issue. I never have this problem when I use my laptop when its not connected to external monitors. Ideas?
UPDATE: After a SMC reset, 50 min later, the same issue occurs. This is a screenshot of the temperature and the activity monitor:
Best Answer
Kernel_task running at an artificially elevated CPU level is the OS's method of forcing the fans to speed up to cool the machine; the side effect is to slow the machine down too, which aids the cooling process.
It can be sign of a hardware issue, but in the case of running 2 external monitors would probably be expected.
You can try resetting the SMC, just in case, but the symptom in itself isn't a sign there is anything wrong.