9800x3d cooling issue

Not sure if I even have a problem or not but cpu seems to be running a bit warm even at idol. Put it through prime95 and I reached 82c and I sit right around 45c at idol. Using corsair titan 360mm aio for cooling and literally 8 year old cooler master thermal paste which I’m thinking is the issue. I also have my radiator mount on the side of my case with fans pulling air through the radiator into the case, I have never tried this orientation before and am worried that maybe partially to blame . I think it’s worth nothing the aio liquid temp never got above 36.4c if Icue link software is to be believed.