Well shit. It had a few hours of stability followed by several freezes. Briefly thought that @TheAquabat had the answer with this:

Quoting: The_Aquabatprocessor.max_cstate=1 rcu_nocbs=0-23 idle=nomwait
or
processor.max_cstate=5 rcu_nocbs=0-23 idle=nomwait

Thanks, though. Here's my dmesg output in hopes somone can see something obvious I'm missing:
https://pastebin.com/2pgiJ52y

Quoting: RossBCTry disabling core boost and precision boost in your bios.

Got a crash within about 5 min :(

Quoting: Liam DaweI would seriously suggest checking the RAM. Most of the time this is a RAM problem.

Tried dropping the RAM to its base frequency as well as max. Sorta took your advice and am replacing the RAM out of desperation for a stable computer. It's been a frustrating experience.

Last edited by brokeassben on 9 June 2021 at 4:53 am UTC

the dmesg log you posted doesnt have anything weird except your drive is failing..ext4 errors

Quoting: Xpanderthe dmesg log you posted doesnt have anything weird except your drive is failing..ext4 errors

Ouch, didn't even think of that. A failing drive could even be an issue.

Quoting: Liam Dawe

Quoting: Xpanderthe dmesg log you posted doesnt have anything weird except your drive is failing..ext4 errors

Ouch, didn't even think of that. A failing drive could even be an issue.

That might explain why Windows is stable since it can't mount that drive. Might also explain why Steam's shader caching will hang for hours at a time. After several years of help desk work, that should have occurred to me 🤦‍♂️ Also just dawned on me that I've had the two platter drives in three different computer builds since 2013 and they've gotten A LOT of use. SMART reporting shows OK health, but several errors including many marked as "pre-fail." Well I feel like an idiot. Going to disconnect the drive and see if that solves all of my woes.