alt Hacker NewsIs this "full" ECC, or just the baseline improved ECC that all DDR5 has?
Either way, on my most recent NAS build, I didn't bother with a server-grade motherboard, figuring that the standard consumer DDR5 ECC was probably good enough.
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layer8 • last Friday at 5:48 PM
The DDR5 on-die ECC doesn’t report memory errors back to the CPU, which is why you would normally want ECC RAM in the first place. Unlike traditional side-band ECC, it also doesn’t protect the memory transfers between CPU and RAM. DDR5 requires the on-die ECC in order to still remain reliable in face of its chip density and speed.
This is full ECC, the CPU supports it (AMD Pro variant).
DDR5 ECC is not good enough. What if you have faulty RAM and ECC is constantly correcting it without you knowing it? There's no value in that. You need the OS to be informed so that you are aware of it. It also does not protect errors which occur between the RAM and the CPU.
This is similar to HDDs using ECC. Without SMART you'd have a problem, but part of SMART is that it allows you to get a count of ECC-corrected errors so that you can be aware of the state of the drive.
True ECC takes the role of SMART in regards of RAM, it's just that it only reports that: ECC-corrected errors.
On a NAS, where you likely store important data, true ECC does add value.