Just to second the recommendations from tomshardware. Been overclocking CPUs and GPUs for decades with thermal paste.
The only thermal death I experienced was a GPU that used tape instead of paste.
Some systems have gone beyond 5 years with no maintenance or replacement of heatsinks or paste. Typical temperature range was 80-85c/175-185f. Usually the paste outlasts the viability of the components to run current programs/OS.