I have been using my PC for a few years and suddenly my CPU temps are idling at ~70C. I have tried changing thermal paste and leaving my pc case panel off, live booting to Linux but still getting the same temps.
CPU: Ryzen 5 3600
CPU Cooler: Stock
Case: Corsair 275R
If you use windows I would check in the task manager for high cpu usage tasks. I would also make sure you don't have steam updating games and such in the background. I would recmmend getting rid of the stock stealth cpu cooler and getting at least a hyper evo 212 black/rgb. It's a tower cooler and I have mounted lots of those in pc builds at work for people.