According to many posts I'm looking for online AMD Ryzen does not support ECC at the CPU level. They advertise their premium Threadripper as support ECC,
Quad-Channel DDR4 ECC Memory Support, With the most memory channels you can get on desktop4, the Ryzen™ Threadripper™ processor can support Workstation Standard DDR4 ECC (Error Checking & Correction Mode) Memory to keep you tight, tuned and perfectly in sync.
But does the Ryzen support it or not?
According to this post, AMD has always provided ECC support in the chips but refuses to validate it (presumably to create a larger value offering in their premium enterprise line). However according to that post which tested this theory they found that of the two types of corrections ECC provides,
The consumer ECC implementation did not cause the motherboard to raise a fatal fault by way of hardware interrupt in the platform. This means the implementation though it exists is incomplete in the tested AM4 platform.
ASUS claim support for a range of AM5 CPUs: https://www.asus.com/me-en/support/FAQ/1045186/ which has been verified by users to work https://old.reddit.com/r/truenas/comments/10lqofy/ecc_support_for_am5_motherboards/
