[seltzered_]

Yeah, these avoton-based boards seemed popular in the freeNAS / diy home server community for being cheap and low power while supporting ecc ram. Even the official freeNAS mini server used (and still used when I checked last year) a supermicro board with an avoton CPU.

[Namidairo]

Websites seem to suggest it's running the C2750, so it does appear to be affected.

[stock_toaster]

Confirmed. I have a FreeNAS mini, and it has a C2750 in it.