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2020 iMac Constant Kernel Panic Crashes whenever using 2nd Monitor
- Thread starter oncilla
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It was mid pandemic when I experienced the “tech support” so all the stores were closed. As soon as they were open again I brought the mac straight into the store. They only give you 15/30 min appointments which isn’t enough time to wipe the mac and reinstall the OS so they have to use speedier solutions
Took my machine to the Apple store again this week. They said they did extensive tests with an external monitor and apparently there were 0 crashes. They told me my issue is "environmental," and nothing is wrong with the hardware or software. They refused to replace motherboard. This is beyond frustrating.
I have been plagued with this issue since I got my late 2020 model in march of 2021. I thought spending 5k on a computer would be the end of problems like this and sadly, I was very wrong. The one fix I have found is that when I’m downloading and uploading files, the error never happens. So now I find myself setting up dummy downloads/uploads that take forever to keep the panic kernel issue from happening. Mac support is a joke and I refuse to go through basic troubleshooting procedures over and over again, or to lose my computer (and livelihood that I need to do work for my business on) by giving it off to their techs in store while I wait around for them to try basic steps that dont seem to work. I hope the downloading strategy can maybe help someone else as it is the only thing I have found that stops the issue, which is weird and beyond me why that stops it, but in 6 months since I started to noticed the possible correlation I never had the system crash while something was downloading
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Just thought I would pop in here - been having the exact same issue as all of you guys since mid-January. Tried all the necessary troubleshooting steps - then went through Apple when that didn't work. Logic board replacement - still crashing. They sent me a brand new iMac - still crashing. I don't know what the hell the deal is with the 5500XT but it's actually insane how commonplace of a problem this seems to be with those iMac models. You'd think Apple would have addressed this by now. I don't even know what to do anymore - going to try that Dell external dock that abad0n suggested, if that doesn't work I guess I'm not using an external monitor.
Try to setup a download/upload between two computers on the same network and slow down the speeds so that it will take a week to download 1GB. Doing that on my system has been the only time I've never had a crash. I've been doing this for months with no issues. The week I tried to stop, multiple crashes. I don't know technical stuff really well but this has worked for me. Good luck
Since yesterday I've had ZERO crashes while using an external monitor with the Dell dock...I'm not sure why these ones specifically prevent crashing but hey it works! It connects to the iMac via USB and then you use HDMI/DP to connect the monitor to the dock. It has its own power supply, and an extra 3 USB ports on the front. You need to install drivers from Dell's site beforehand. HUGE thanks to @abad0n for the suggestion. Kinda crazy that all this troubleshooting, stress, and trips to the Apple Store the last 3 months could have been solved immediately with a simple dock. Live and learn I guess...
This is the one I got, sucks we have to shell out another $145 on top of an expensive iMac but it beats having to buy an entirely new machine. If you want the newer model, there's this one as well for $230.
PLEASE spread the word about this dock to anyone with the 5500XT iMac...seems to be the only concrete solution along with @RickGarrabrant download/upload fix.
This is the one I got, sucks we have to shell out another $145 on top of an expensive iMac but it beats having to buy an entirely new machine. If you want the newer model, there's this one as well for $230.
PLEASE spread the word about this dock to anyone with the 5500XT iMac...seems to be the only concrete solution along with @RickGarrabrant download/upload fix.
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Hi all. First-time poster here--- wanted to thank everyone in the above thread for sharing their experiences & solutions (as well as dead-end Genius Bar "support" experiences) as it has helped me understand what is happening with my system.
For the sake of contributing to the knowledge-base on this topic:
System: Nov 2020 iMac (Retina, 5K, 27", 3.8 GHz 8-core i7, 32 GB RAM, Radeon Pro 570 8 GB graphics.)
Issue: Unlike many of you, my GPU Kernel issues didn't begin out of the box. The issues arose _very suddenly_ in probably January of this year--- after about 13-15 months of heavy/daily usage w/o change in what I was doing.
I use multiple displays (1080p 24" Samsung, 27" 1080p Samsung) for multitasking. I'm a writer and often keep multiple windows of drafts, notes, or references up on the 27" Sam, primary document on the 24" Sam, and then native 5K 27" is typically for video content (Netflix, Hulu, YouTube, or local files through VLC, etc.). I use Google Chrome, and have way-too-many tabs open; often I'd have 5 or more tabs of video streaming at once (I have atypical sensory needs), such as multiple YouTube windows, or 5+ Twitch streams, etc. For more than a year, this was a totally fine usage with no issues. Then 2022 came in and had other ideas.
Quick note, that I did have issues with one (or both) of my external monitors "bouncing" its connection (HDMI to an Anker hub to USB-C to the computer), leaving the screen blank as though disconnected. Unplugging-and-then-replugging the HDMI cable typically did the trick, but it was "hair trigger" during this time: if the hub was moved or the plugs got even slightly tapped (such as when plugging in a thumb-drive beside them) this would bounce the connection again. This problem vanished, as far as I recall sort of all on its own, and then the OTHER issues (which brought me to this thread) arose.
The slow-downs and kernel_task thermal throttling made work on the system impossible. The "triggers" always involved some degree of heightened GPU activity -- video, crap like GIFs on Discord servers, and Facebook in Chrome -- and was resolvable (without a crash/shut-down) so long as I caught it in time, and suspended those processes. (Closing out the offending application/tab/window, or sometimes just pausing video for a bit, often made a difference for a little while. Resetting the system altogether, or bouncing Chrome -- in other words ending/terminating processes -- also worked, but the issue kept arising. It never occurred to me that this could be from multiple displays.)
Presently attempting to recreate the issue on just the native display: no issues. (Local HD video through VLC, multiple YouTube tabs, Netflix, all playing/streaming at highest quality available, plus Discord + Facebook, etc.) I'm keeping an eye on activity monitor, and ALL levels of CPU usage are staying significantly below concerning levels---I'm only a day into this test, but so far, this isolated the primary area of issue. I'll be buying the Dell D6000 (thanks for that!) as others have recommended, and seeing how that goes for me; will report results of that here (for future readers/trouble-shooters).
I have zero gaming, or Adobe, or graphics/video editing (or rasterizing, complex rendering, etc) applications running: very straight forward and isolated usages. Word processing, Discord, email, and Chrome. (FB is a notorious resource hog and that has often been the "straw to camel's back" for causing the kernel issue for me: if I had no FB tab open, and only video, it reduced instances of the issue by probably 50% or more, but FB on its own would not create the issue.)
[As an aside: I had similar issues with an external display on my 2013 MPB in 2019; at the time I had assumed that these issues were related to the age of the system, so I never committed serious effort to resolving it. (The triggers there were always involving an external display, and graphics-heavy stuff: in that cast, it was some Steam games, typically NWN:EE, and sometimes a Windows simulator (WINE, for running NWN Toolset on a Mac). I never tried to resolve those things, but may well give it a go through just to see if it happens to be the same thing as the iMac.]
Thanks again for such a thorough walk-through of similar/related issues. For now, I'm assuming that my issue is more closely related to what all of you are experiencing than not, whether or not it is exactly the same thing. Will update once I've got my D6000 and see what that does.
For the sake of contributing to the knowledge-base on this topic:
System: Nov 2020 iMac (Retina, 5K, 27", 3.8 GHz 8-core i7, 32 GB RAM, Radeon Pro 570 8 GB graphics.)
Issue: Unlike many of you, my GPU Kernel issues didn't begin out of the box. The issues arose _very suddenly_ in probably January of this year--- after about 13-15 months of heavy/daily usage w/o change in what I was doing.
I use multiple displays (1080p 24" Samsung, 27" 1080p Samsung) for multitasking. I'm a writer and often keep multiple windows of drafts, notes, or references up on the 27" Sam, primary document on the 24" Sam, and then native 5K 27" is typically for video content (Netflix, Hulu, YouTube, or local files through VLC, etc.). I use Google Chrome, and have way-too-many tabs open; often I'd have 5 or more tabs of video streaming at once (I have atypical sensory needs), such as multiple YouTube windows, or 5+ Twitch streams, etc. For more than a year, this was a totally fine usage with no issues. Then 2022 came in and had other ideas.
Quick note, that I did have issues with one (or both) of my external monitors "bouncing" its connection (HDMI to an Anker hub to USB-C to the computer), leaving the screen blank as though disconnected. Unplugging-and-then-replugging the HDMI cable typically did the trick, but it was "hair trigger" during this time: if the hub was moved or the plugs got even slightly tapped (such as when plugging in a thumb-drive beside them) this would bounce the connection again. This problem vanished, as far as I recall sort of all on its own, and then the OTHER issues (which brought me to this thread) arose.
The slow-downs and kernel_task thermal throttling made work on the system impossible. The "triggers" always involved some degree of heightened GPU activity -- video, crap like GIFs on Discord servers, and Facebook in Chrome -- and was resolvable (without a crash/shut-down) so long as I caught it in time, and suspended those processes. (Closing out the offending application/tab/window, or sometimes just pausing video for a bit, often made a difference for a little while. Resetting the system altogether, or bouncing Chrome -- in other words ending/terminating processes -- also worked, but the issue kept arising. It never occurred to me that this could be from multiple displays.)
Presently attempting to recreate the issue on just the native display: no issues. (Local HD video through VLC, multiple YouTube tabs, Netflix, all playing/streaming at highest quality available, plus Discord + Facebook, etc.) I'm keeping an eye on activity monitor, and ALL levels of CPU usage are staying significantly below concerning levels---I'm only a day into this test, but so far, this isolated the primary area of issue. I'll be buying the Dell D6000 (thanks for that!) as others have recommended, and seeing how that goes for me; will report results of that here (for future readers/trouble-shooters).
I have zero gaming, or Adobe, or graphics/video editing (or rasterizing, complex rendering, etc) applications running: very straight forward and isolated usages. Word processing, Discord, email, and Chrome. (FB is a notorious resource hog and that has often been the "straw to camel's back" for causing the kernel issue for me: if I had no FB tab open, and only video, it reduced instances of the issue by probably 50% or more, but FB on its own would not create the issue.)
[As an aside: I had similar issues with an external display on my 2013 MPB in 2019; at the time I had assumed that these issues were related to the age of the system, so I never committed serious effort to resolving it. (The triggers there were always involving an external display, and graphics-heavy stuff: in that cast, it was some Steam games, typically NWN:EE, and sometimes a Windows simulator (WINE, for running NWN Toolset on a Mac). I never tried to resolve those things, but may well give it a go through just to see if it happens to be the same thing as the iMac.]
Thanks again for such a thorough walk-through of similar/related issues. For now, I'm assuming that my issue is more closely related to what all of you are experiencing than not, whether or not it is exactly the same thing. Will update once I've got my D6000 and see what that does.
So far so good. D6000 set up yesterday. External Samsung monitors connected up (HDMI -> DP via active adapters -> D6000) and, thus far, no recurrent issues. A bit wonky getting the DisplayLink drivers to recognize the displays in Big Sur (requiring system shut-downs rather than system restarts), but no issues. An odd thing that I noticed while setting this all up: my two Anker USB-C hubs (which I had previously used to run my HDMI monitors into the system) were piping hot when I disconnected them from the computer, despite nothing being plugged into them--- they were running hot just being plugged into the iMac. Is it possible that the iMac has issues in handling USB power/thermal levels? The heat coming off of the Anker units was what I'd expect from a hub actively full up on devices and tasks; these were empty. I've also noticed that other USB devices -- DasKeyboard & Logitech webcam -- "run hot" when plugged in directly to the computer, but I had previously just assumed that these devices ran hotter than expected.
(I'm still under my AppleCare period so I will _also_ be dealing with Geniusbar nonsense moving forward, but didn't expect that to resolve my external display/kernel issues. Curious if anyone else has had issues with peripherals running hotter than expected.)
(I'm still under my AppleCare period so I will _also_ be dealing with Geniusbar nonsense moving forward, but didn't expect that to resolve my external display/kernel issues. Curious if anyone else has had issues with peripherals running hotter than expected.)
Update: My 2020 iMac's kernel panic problem seems to have died down after changing the external monitor. I previously used a drawing tablet (also used as an external monitor) that connected to my iMac through HDMI connection, which I did so using usb-c hub. I now changed to a drawing tablet / external monitor that connects directly to my iMac with usb-c connection and I'm not experiencing any of the random shut downs. My previous machine was from xp-pen, current one is Wacom.
I have two 2020 imacs that I bought for work that have been doing this for months now. I'm probably going to get the Dell dock, I'm just curious how all the connections are made? I understand HDMI from the 2nd monitor to the dock, but what goes from the dock to the imac? I thought thunderbolt was the only option for connecting a second monitor, and I don't see any thunderbold ports on the D6000.
Am having good luck so far using the d6000 dock. In fact I'm now running 2 externals, and no panics as of yet. (it's only been a day but it "feels" right if that makes any sense. Had some issues with a display port to HDMI connection, but got some additional new cables (VGA to display port and display port to display port) and all is working well so far. The externals are old. Like the Viewsonic is from 2003 I think, the Dell is from 2015 maybe. So nice (crossing fingers) that I now have multiple monitors with tons of real estate to work from. Thanks abad0n!
Good news, Ross! It's one small step for man... etc. I will probably follow your lead and get one of those docks. Thanks!
Hi All
I am also experiencing kernel panics. No external monitors involved however I am running a thunderbolt attached storage array.
Wondering if there may be a relationship as I am having no joy with Apple. Have tried different memory brands, replaced main logic board, endless upgrade to the latest release recommendations and a case open with Apple since at least last October.
Any help appreciated.
I am also experiencing kernel panics. No external monitors involved however I am running a thunderbolt attached storage array.
Wondering if there may be a relationship as I am having no joy with Apple. Have tried different memory brands, replaced main logic board, endless upgrade to the latest release recommendations and a case open with Apple since at least last October.
Any help appreciated.
Ive been having excellent luck with the d6000, however I have had a couple of crashes when my external hard drive is plugged in. It's almost like the machine just runs out of memory or something. then blinks out. when the drive isn't plugged in I have zero crashes. also with the drive plugged in, I'm still having only a couple of crashes since June 2. FWIW.
Since one of the latest updates of macOS Big Sur, I had no crashes anymore. I use a 2020 iMac with the 5500xt graphics card and an external monitor via usb-c to DisplayPort adapter.
I am following threads about this topic for a while now (since about 1,5 years). I am working on my PHD thesis at least 5 days a week in this time with several apps open simultaneously (Safari with a lot of tabs, multiple office document (Word, Excel, PP), Parallels running Windows apps (i.e. statistics software), VPN clients, reference manager, mail, sometimes image processing, etc.). I experienced a lot of crashes, but they seemed to happen randomly, sometimes >1 a day, then some days in a row with no crashes. Since the latest updates (at least since 11.6.8) I had no crashes anymore. I didn't change anything else in between at my setup.
PS: I am still on Big Sur because of reports that OneDrive works differently on Monterrey, and all my thesis-data is stored in Onedrive so I didn't want to risk anything ...
I am following threads about this topic for a while now (since about 1,5 years). I am working on my PHD thesis at least 5 days a week in this time with several apps open simultaneously (Safari with a lot of tabs, multiple office document (Word, Excel, PP), Parallels running Windows apps (i.e. statistics software), VPN clients, reference manager, mail, sometimes image processing, etc.). I experienced a lot of crashes, but they seemed to happen randomly, sometimes >1 a day, then some days in a row with no crashes. Since the latest updates (at least since 11.6.8) I had no crashes anymore. I didn't change anything else in between at my setup.
PS: I am still on Big Sur because of reports that OneDrive works differently on Monterrey, and all my thesis-data is stored in Onedrive so I didn't want to risk anything ...
That is interesting, your 2019 does not have a T2 coprocessor or an RDNA based AMD GPU which eliminates two of the more popular theories about the case of all the KPs. How is the second monitor connected on a 2019?
Sadly, after at least 2 months without crashes, it happened again. So it seems that I was wrong and it wasn't solved by one of the last updates. So I have to consider a solution á la Dell d6000, more or less an external graphics card, or ask for a repair.
Does anyone got a warranty-repair after expiration of the Apple 1-year warranty due to EU-consumer law, which mandates a two year warranty, but you have to proof yourself that the causing issue was already present at the time the device was bought (which is easy because of this forum thread and numerous threads in other forums). I bought my iMac in November 2020 ...
Finally found others having the same issues I have been having! At least I feel we can probably figure this out amongst ourselves seeing as Apple Care and the Genius Bar has proven to be worthless.
I started getting both my external and iMac screens going black almost as soon as I updated from Catalina to Big Sur on my then new 2020 27" Retina iMac. Same story as everyone here when it comes to getting Apple Care support....reset the PRAM, SMC, unplug all peripherals, unplug power...all of it. Sometimes I get a KP crash as frequent as 5 times a day with stretches of weeks in between. It happens at random times no matter what app I am running..or not running any apps at all. It's incredibly frustrating. Whom here has had any long term success at getting their system KP free?
I started getting both my external and iMac screens going black almost as soon as I updated from Catalina to Big Sur on my then new 2020 27" Retina iMac. Same story as everyone here when it comes to getting Apple Care support....reset the PRAM, SMC, unplug all peripherals, unplug power...all of it. Sometimes I get a KP crash as frequent as 5 times a day with stretches of weeks in between. It happens at random times no matter what app I am running..or not running any apps at all. It's incredibly frustrating. Whom here has had any long term success at getting their system KP free?
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I have Apple Care and they do not even want to acknowledge any of the forum posts with regards to this issue. when ever I mentioned it they would either not replay or say that they were not aware of any issues. I find that hard to believe and very discouraging.
Frequent reader of these forums, but signed up just to reply to this thread to give some hope.
This same problem has plagued me since I got my 2020 27" i7 with the Radeon Pro 5500 XT in December of 2020. For long stretches of that time, I just went without my second screen, which was far from ideal for the work I do (design). Every time Apple updated macOS, I'd give it a shot again, hoping they updated the driver and it would be fixed and it always ended up crashing again after a few hours or days if I was lucky, and I would give up again.
After seeing a handful of posts here and elsewhere about some success with the Dell D6000 Docking Station I decided to try it. Absolutely hated to waste more money on this troubled system, but also not that interested in upgrading this soon or the Studio line in general, so I bit the bullet and found one on eBay for an ok price.
A little over two months in and I have had zero crashes. Not one. People have mentioned that plugging an external drive into the D6000 seems to lead to the crashing again, and I hate to waste a good dock, but I am literally just using it for the monitor and nothing else, and my problem seems to finally be solved.
This same problem has plagued me since I got my 2020 27" i7 with the Radeon Pro 5500 XT in December of 2020. For long stretches of that time, I just went without my second screen, which was far from ideal for the work I do (design). Every time Apple updated macOS, I'd give it a shot again, hoping they updated the driver and it would be fixed and it always ended up crashing again after a few hours or days if I was lucky, and I would give up again.
After seeing a handful of posts here and elsewhere about some success with the Dell D6000 Docking Station I decided to try it. Absolutely hated to waste more money on this troubled system, but also not that interested in upgrading this soon or the Studio line in general, so I bit the bullet and found one on eBay for an ok price.
A little over two months in and I have had zero crashes. Not one. People have mentioned that plugging an external drive into the D6000 seems to lead to the crashing again, and I hate to waste a good dock, but I am literally just using it for the monitor and nothing else, and my problem seems to finally be solved.
Same experience here with a 2020 27" i9 and a Radeon Pro 5500 XT. For two years I experienced sporadic but recurring crashes whenever I used a second monitor (27" LG 4k, connected with a DP to Thunderbolt cable). I bought the D6000 dock about a month ago and the crashes ceased.