Spike in CPU temperature for 10 seconds with LOW CPU usage

I have a Ryzen 9 5900x that typically sits around 65c max during gaming under a NH-D15. Have had zero issues with my set-up in the past, until D4.

Every few minutes (anywhere between 1 minute to 5) it’ll randomly spike to almost 80c for just a second or two before going back down to usual temps. Doesn’t seem to matter where I am or what I’m doing.

CPU usage is never higher than 20-25%, and does not change during the temp spikes.

Performance is otherwise fine, but it’s very jarring having my case fans go haywire intermittently like this. GPU temps have so far been normal.

This did not happen during the Beta or Server Slam.

I have my own thread going about this, here.