Thanks chew* for hints! I will experiment a lot more in due time, but I suffer from chronic lack of time to play properly with my PC lately ... It only took me 4 days to even start playing with memory timings and basic OC
Holidays would help here, but they are 2 months away!

I'm now very happy with DDR4 3333MHz CL14 1 day stable system. Next step for me is to play with main CL timings to see how good my RAM and CPU uncore are
BTW moving from Haswell 4.4GHz daily to so far 3.8GHz Ryzen feels like the right thing to do. Almost anything plays and runs as good or better already, considering I play with 144FPS cap to match my 144Hz screen and my W10 install is as old as Windows 10 itself!