drive_bandit

I stumbled upon this thread have having the exact same issues for a while now. Religiously, around the 45 day mark my server would reboot. Nothing in the logs. Just an unclean reboot. Same steps as OP; changed my RAM timings, C-States, ASPM then fully changed RAM, motherboard, CPU. Same thing. Started to wonder whether it was the ConnectX-3, LSI HBA or 3060Ti but couldn't find anyone mentioning these as triggers for reboots. What I do have in common with OP is the TP-Link KASA smart plug! I'm using a EP25 which is basically the same as the KP115. This would explain the lack of logs and the reboot. It would never have occurred to me had OP not mentioned it. I agree with with him that there must be something in the smart plug causing a momentary brown out which seems to happen every 45 days. I've removed and it will see if it reboots again but I have to wait for the 45 days. I'll update if it reboots again. OP, do you have the smart plug between the server and a UPS? That's my current set-up so maybe it's a smart plug / UPS interaction which is the true culprit?