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CPU Throtting 800 MHz 2018 i9 Mac Book Pro

ElijahGlo

macrumors newbie
Original poster
Oct 25, 2016
6
0
I'm seeing an issue with my 2018 MacBook Pro i9 spec'd machine. I don't think it's temperature related, thinking more voltage drain. Interested to see if anyone else has the same issues. Current setup is 80W . USB apple charger and 1x 4k screen connected via DisplayPort.

Intel Power Gadget reports 0.8 GHz core clock, and kernal_task eats 99% of the CPU until the screen is unplugged and plugged in again.

Screenshots uploaded
https://imgur.com/a/aI922fy
 

internetrando

macrumors 6502
Jun 5, 2018
471
271
Texas
That's...not how that's supposed to work.

It looks like your fans are running at full speed too?

I would try a restart first considering that your system is reporting to have been awake for over eight days. If that does not resolve it, I would recommend performing a SMC reset. The process is different for the 2018 models.

https://support.apple.com/en-us/HT201295
 
Comment

deadworlds

macrumors 65816
Jun 15, 2007
1,026
757
Citrus Heights,CA
Kernel task using a majority of your CPU usually means that some other process has gone rouge and has been using excessive amounts of CPU cycles and causing excessive heat as a result.

kernel task attempts to take control of the CPU cycles but doesn’t perform any actual processing, hence why your CPU is down clocked to 800mhz. Usually a restart/killing the rouge process or waiting a few minutes resolves the issue.
 
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leman

macrumors G5
Oct 14, 2008
12,359
7,381
Try resetting SMC, if this doesn’t work i’d RMA it. Does this behavior only occur with Citrix, or do you also see it when running other stuff? Try for example starting cinebench (it’s a free download). You need to rule out that it’s Citrix doing something weird.
 
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ElijahGlo

macrumors newbie
Original poster
Oct 25, 2016
6
0
Apple has been notified of the issue, their engineering team are following up. Nothing to do with Citrix, it just appeared in the screenshot as next to iStatMenus. You can't kill kernal_task it's part of the main OS and even then eating the CPU is caused by a base clock speed of 800 MHz.
 
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colincjw

macrumors newbie
Jul 31, 2013
13
1
Apple has been notified of the issue, their engineering team are following up. Nothing to do with Citrix, it just appeared in the screenshot as next to iStatMenus. You can't kill kernal_task it's part of the main OS and even then eating the CPU is caused by a base clock speed of 800 MHz.

You're not the only one. Facing this massive bummer here every week with throttling ranging from 800mhz to 1.0ghz. The engineers I spoke to can't seem to identify the root cause but advised to take it in.




Guess I'm gonna take it in, but do keep me posted if you hear from them!
 
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