I've tried 1.2V SoC, and it still had memory errors. However, I pulled the DIMMs out to test them on a Intel system (and it worked with XMP profile), and ever since I put them back in the AMD system, there are no errors anymore, even at 3600MHz with 1.1V SoC (Uptime: 4 days 23:22:53).
I think I swapped the DIMMs in the process and they pair better now. This is so sensitive.
Is this a common problem for AMD memory controller? Should I RMA CPU?
I bought the CPU resealed and tested by the merchant for a "better" deal. I shouldn't have done this ... Now I'm worried that if I RMA, I'll get an even worse resealed one. Ughhh!