3333MHz on 1 dimm per channel, single rank and Samsung B die, using The Stilt's Fast UHQ timings, I use 1.05V SOC. I can pass ~9hrs GSAT / HCI Memtest with SOC: 1V, IBT AVX custom 13312MB needs SOC: 1.05V for pass. The f@h screenies posted earlier are same CPU, setup. Another CPU needed ~1.075V. Both R7 1700, rest HW same.
Black screen can be VCORE as well, maybe a tweak of VCORE will allow lower SOC.
I'm not familiar with the Gigabyte x370 gaming 5, sorry. On the C6H some members did see as UEFI improved, especially where AGESA has changed. Which besides having CPU Microcode / SMU firmware changes includes IMC firmware updates. That SOC came down for some, so perhaps same will happen in your case.
1.1V is a guidance by The Stilt, as always it could be some need more, from what I have seen tends to be people with >16GB and/or > 1DPC / DR RAM setup. ASUS "team" on OCN have stated MAX 1.2V. IIRC Gigabyte has stated MAX 1.3V. IIRC Robert Hallock in video linked before 1.2V.
For me for 24/7 use I like to be at ≤1.1V. I have tested upto ~3500MHz in GSAT / HCI memtest on 2 R7 1700 CPUs, both needed ~1.125V to 1.15V. Which for me on daily use I wouldn't want. Reason being the performance gain IMO doesn't justify the voltage increase. Also I can not get above 3333MHz as tight as that RAM MHz.
Perhaps drop to 3200MHz with tight setup, you'll lose little IMO and gain on lowering voltages. Look at the last image in
this post, performance % between 3200MHz and 3333MHz is very close to non existent in test cases. Next I've edited the image from AMD Community article with % marked of gain vs 3200MHz C14 AUTO BGS Off.
I reckon with sub timings tight on even 3200MHz C14 you'll close the gap to half % shown on image. Perhaps a later UEFI will then allow you to revisit 3333MHz tight setup and have no issues with lower SOC than used currently.
I said "some tosh", ie some info is nonsense. I have explained 2 points which I felt were wrongly explained, many will view the video and many will not have the correct advice from that. There is another point I could mention but really I reckon no need to as I don't wish to "rock the boat".
Thank you for analysis of my character, as I know I am not arrogant I'll ignore it. I wish you well

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