The same thing was happening with my GPU so I underclocked and undervolted it to hell using msi afterburner and now instead of getting 85 C during gaming sessions it’s around 70 C. my CPU fan is always loud. i think the thermal paste is gone. I’m not willing to take my computer apart because where my computer is it’s really awkward. rn the package temp is idling at 46-55 C, jumping every second. min temp is 45 C. the max temp is 80 C idling. i’m getting spikes in high temperature that last a second or so but when I’m playing a game it can spike to 95-100 C
I’d say clean it every year, maybe twice but monthly seems like you’d be wandering on the slope of a possible accidents.
I have never changed the paste (I do put in good stuff from the beginning) but I’d do if I detected temp changs ofc.