Asrock 970M Pro 3. Best mATX for AM3+

AMD Overdrive is not a very good stress test in the sense that it doesn't push your system very hard. Compared to Prime95, my CPU is running ~8C cooler (43C) and my socket is ~12C (56C) cooler when running all stability tests AMDOD has (as well as writing this post). And this is with all fans spinning at full rpm all the time, regardless of the temps. Based on your temps at stock speeds and stock voltages, I'd say your system is not 100% stable under heavy loads when using the OC settings you mentioned. But if AMDOD stable is good enough for your everyday use, then who am I to argue.

Thanks for the clarification regarding the temps, now it makes sense. It seemed a bit odd that your CPU would be at 52C when undervolting, so I wasn't sure if that statement really was connected to the undervolting or if it was a general statement concerning all of your testing. Regarding undervolting, the same comment applies as above: If you're using AMDOD for stability testing, then your system can still be unstable under heavy use. Whether or not that matters depends on what you do with your PC.