Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

blizaine

macrumors 6502
Original poster
Sep 17, 2003
355
157
Hi guys,
I have a strange issue with my 2019 iMac. It is an Intel 9th-gen i9 w/ 16GB of RAM and Apple's fusion drive. I recently purchased a Sabrent 2TB Rocket NVMe 4.0 Gen4 PCIe M.2 SSD with a TREBLEET Thunderbolt3 to NVME M.2 enclosure. Formatted as APFS with GUID and it is smoking fast (~2300GB Read & Write). I installed Catalina on it and everything seemed really great for a while, maybe about 2 hours or so. Then the iMac Kernal Panic'd. I've tried both TB3 ports and it will boot and work for a while and then crash. I thought maybe the drive was getting too hot, so I installed MenuStat to view temps and it never really got above 53 degrees (Celcius) under heavy load. I thought it might just be a faulty SSD or enclosure. To confirm it was (or wasn't), I plugged it into a 2017 MBP 15", i7, and it boots and has no issues. I've run it for a few days without issues at this point. Going back and booting it with my 2019 iMac, it only runs for 20-30 min before freezing up. Resetting NVRAM didn't help. Any other suggestions? I've considered installing it internally, but upgrading the fusion drive in a 2019 iMac looks pretty invasive, so that's my last resort. Thanks for any suggestions.
 
Update: It looks like I might have been barking up the wrong tree... I decided to do a fresh install of MacOS onto the internal Fusion drive and just use that until I can figure out a solution to the freezing while booted from the TB3 drive, and guess what? My iMac freezes using that drive as well. Usually after a few hours. I'm running a MemTest86 now but it is almost done with no errors. Does anyone have thoughts on what else it could be? I also ran the Apple Diagnostics (press D on boot) and it was fine. Of course, I just realized I purchased this thing in June of 2019 so no more warranty.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.