Thanks for the reply! It does seem like, from my research, that the Asus boards (specifically Prime, but probably all of them) support ECC completely. But as you said, this information is not centralized anywhere. Just random forum posts like this.

My server needs an overhaul (Ivy Bridge Xeon + 8GB ram). I’ve been thinking of using Zen 3 too, since Zen 4 is too expensive. What motherboard and memory modules are you using? And did you verify that ECC corrections and errors are sent to the OS (more info: https://hardwarecanucks.com/cpu-motherboard/ecc-memory-amds-ryzen-deep-dive/5/)?