Have you applied a Cooling paste to the cooler?
50-55 is a fine temperature when you are playing games and benchmarks, but you need to check it when it has no load too.
These components have a large amount of power flowing through them, so high temperatures are not unexpected anymore, and unless you are using water-cooling or some more exotic method to cool, 40-60 degrees can be expected.
Most Motherboards go into alert when the temperature gets to around 65+ but 75 is generally an auto throttle or shutdown temp.
The Bigger the CPU/ using Intel can run hotter than AMD, but if you are using a Graphics solution that is integrated on the chip, it can get hot fast.
But Make sure that the Thermal paste is applied to help power dissipation, that helps!