I have a similar problem. About every hour, my pc laggs AF with no aparent reason (even while just watching youtube). I have a temperature monitor (Core Temp) constantly running in the background with a Rainmeter skin that turns it into a graph. I took a look when one of this lagg spikes happened and there was an irrational temperature spike in the CPU of 229ºC (WTF)
If you look at the graph you can see that it is a sensor failure since it instantly comes back to idle temps but it thermal-throttles for seconds while it comes back. It even disconnected me once from GTA Online.
Im currently trying to get a solution from AMD, whenever i find a solution i will tell you if you can aply it to yourself
