Ryzen 3 1200 Overclocking Help

[Frostalz]

I have had my PC for around 3 weeks and I have been experimenting with the overclocking of my Ryzen 3 1200. The Default clock and voltage is 3.1 GHz and 1.18750 V. When I first overclocked my CPU I set it to 3.8GHz and at 1.21875 V. I was able to run and complete Cinebench but after a few days I ran Cinebench once again and my PC black screened, suggesting that it was a unstable overclock. So I raised the Voltage to 1.22500 where the same scenario happened. Now I have gone up to 1.25625 and CPU demanding games oftenly Black Screen and make the PC unresponsive, however audio from Skype, music ETC. is still being transmitted and my friends still are able to hear me through Voice coms.
I need a solution to this and require suggestions for a stable overclock or did I just get very very unlucky in the silicon lottery or this another problem in the software or other hardware.

 

[brad.rappa]

Ryzen 3 1200, 1.281 V, 3.8GHZ OC. Playing any game from Fallout4 to DOOM I get to around 44C with an ambient temp of about 32C.

Normal Operating Temp is anywhere from 32C to 38C. It's all about the thermal paste, I had to re-do mine. I watched a YouTube where a guy took a piece of square glass and used all the different methods and the one that got the best coverage was the 5 dots like on the side of a 6 sided die. Have always used it, never fails me.