Well yes, I believe all Vega 56s have hynix while the 64s have samsung memory. That's the reason why I buy 64s even though the 56s are cheaper. From my experience samsung memory always seems more robust and has fewer crashes. It's probably also why the 56 even with a 64 bios hashes a bit less than the 64. So basically my point remains.. We weren't even talking about the 56s.
Check this article out: https://videocardz.com/72173/there-are-at-least-three-variants-of-vega-10-gpu-packages
Either way, there are definitely 56s with Samsung (another). But now you have me wondering about the weaker cards in my fleet.