Basically your idle temps will be higher even with AoI cooler in order to have a quite machine. It starts to speed up only when ur CPU is under heavy LOAD and really needs to cool down.
Ur idle temps are that high because your cooling pump and fan are going at very low speeds within 30-50c as these temps are completely OK - it is called silent mode - you can have maxed pump and fan settings even when you have 30c (it would result in improving idle temps drastically - maybe under 30c, but that is not necessary and it would only make your computer very loud in every situation even when your CPU is doing nothing), so even if ur idle temps are about 50c - it is completely fine. Only what matters are top long term temps under stress tests / benchmarks - good CPUs can handle even over 80c. My can handle even 100c when I am testing something, but I have a great chip, I am a lucky one.
50-60c are nothing when under load - good CPU can go between 65-75 without no lifespan degradation. For CPU, risky temps are over 80-90+. So in your case, you are completely okay.
Actually its a shame you cannot OC your CPU. 60c under load is a huge temperature reserve for OC. You could OC until you would get 75c under load and then it would be best you could get out of that CPU.