What do you have for a case and what do you have for case fans? What sort of ambient temperature are we talking about? Are you working outside in Antarctica or perhaps the Mojave desert? What do you have for a cpu cooler? What games are you playing? What do you have for a GPU?
Lots of questions, but to ease your mind, those temps aren't too high or in any way outrageous, unless you're outside in Antarctica. When did you notice a "perceived" performance loss? Have you done any benchmarks with before or after numbers to corroborate?
To aid our investigation, give us lots of info, if you could on your system(memory, mobo, GPU, storage and boot drives, and PSU). Also, if you could include a description of the sorts of system maintenance you do, that would also help.