Super tired of kernel panics on my 2020 27" iMac. Do I have a lemon?

I also own the 2020 27" iMac and I too had the exact same problem for three months. You may not like my answer, but my problem was caused by OWC RAM. There's something about OWC that is not playing nice with the 2020 iMacs and neither Apple nor OWC is coming clean about it.

I had the reseller upgrade the RAM to 128GB of OWC RAM at purchase. Same symptoms as yours and more. Multiple times to Apple repair with no problems found.

Install OEM 8GB RAM back, and it works fine. Install any OWC RAM two sticks, or all four and the machine would crash minutes into using Lightroom/Photoshop/FCP

As a desperate attempt, I purchased 128GB of Micron RAM (Apple OEM) via Crucial and within minutes, it resolved all the problems. It also resulted in a drastic reduction in my iMac's temperature and the fan speed would go to idle (1200rpm) where with OWC RAM, my iMac's would stay consistently stay above 2400rpm idle. OWC replaced my RAM twice, and still did not improve.

Many people had this exactly problem, and ditching OWC with Micron resolved it.

Thankfully, the reseller I purchased my iMac from (and upgraded the RAM) refunded my money for the OWC RAM. I was lucky. I know OWC has a very little window to return for a full refund.

For three months, my iMac would crash multiple times per day. The moment I installed Micron RAM 14 months ago, my iMac has run stable, cooler, and much quieter.

Here's the very large discussion about it:

https://discussions.apple.com/thread/251962728?answerId=254170742022&page=1

You had the kernel panics with just the Apple RAM installed, right. If so then the problem is probably software related.

CleanMyMac is considered by most here to be akin to malware. Uninstall it according to the developer's instructions. lt will only add to the problem your having.

Then download and run Etrecheck.  Copy and paste the results into your reply. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the first window that comes up so that it can get additional information from the Console and log files for the report:

Also click the About… vurron and read the info to further permit full disk access.

Copy/Share the report

and use the Additional Text button to include the report in your reply.

like this:

Welcome to the Apple Support Communities.

You have two issues:

CleanMyMac:

Delete CleanMyMac: How to uninstall CleanMyMac X & How to Delete Anti-Virus, Cleaners, VPNs,… - Apple Community.

Mac computers do not need any sort of anti-virus, cleaners, VPNs, etc. The only thing they are good at is creating false marketing promises and taking consumers' money. In fact, anti-virus and other cleaners cause performance issues, security issues, and make macOS appear buggy. Your Mac is far worse with these types of Apps installed.

Mac computers have protection built-in, which is the best protection for your Mac. For specifics on macOS Security, see: macOS - Security - Apple and Protecting against malware in macOS - Apple Support. Mac computers also have built-in storage recommendations: Optimize storage space on your Mac - Apple Support. You can even use the built-in macOS Firewall: Block connections to your Mac with a firewall - Apple Support. Other than that, all you should do is restart your Mac approximately once a week and keep macOS up to date: Update macOS on Mac - Apple Support. 

However, should you ever get adware or malware on your Mac, the only tool that should be used to remove it is the free Malwarebytes for Mac. This App is the only exception to the general rule that no anti-virus, anti-malware, etc. should be used.

OWC Memory

OWC Memory is known to have issues in the iMac (Retina 5K, 27-inch, 2020). Replace with either Apple Memory or Crucial Memory.

Jack

boesejean wrote:

Etrecheck also looks like malware to me. Not gonna use it.

EtreCheck is NOT malware, and I also suggest you create a report and upload it.

CleanMyMac IS akin to malware and needs to go.

Jack

One more thing, you can order Micron RAM and try it out. They have a 14-day return window and you'll know the first day if it works.

I don't think it's the OWC RAM. It was determined that when using both the OWC and Apple RAM the problem would occur. I'm thinking it's more a software issue due to the fact that it occurred with only the Apple RAM installed. That's why I suggested the Etrecheck report.

It's not on the Apple store because Apple requires it to be so severely hobbled that it can't get the necessary information needed to do a good evaluation of the system and software. This is what the report looks like.

You'll notice that even the drive names are not included, only the first and last letter of the name fill in with asterisks (*): Drive Toad Hall ends up T*******l. No personal info included.

Without it we can' begin to help you.

Hard to say. We have a pair of 2020 27" iMacs (Retina 5k, 3.3 Ghz, 6 core, 16GB RAM) and I've had a two KPs for no apparent reason; wife hasn't any far as I know. Both are running Monterey 12.2 beautifully.

Same is true for my old Late 21.5" Retina and our 13" MBPs (2016 and 2020); don't remember any.

All are Intel