The specs claim "ECC" [0], but give no further details. ejolson on the Raspberry Pi forums [1] thinks it is on-die ECC, not traditional ECC, which would mean transfers between the RAM and the memory controller are not protected and there is no means of monitoring errors. Some discussion on Reddit [2] also suggests it's on-die ECC. If this is true, it's better than nothing but still not a replacement for a NAS with traditional ECC RAM.

[0] https://www.raspberrypi.com/products/compute-module-5/?varia...

[1] https://forums.raspberrypi.com/viewtopic.php?p=2296449#p2296...

[2] https://old.reddit.com/r/raspberry_pi/comments/1irryax/raspb...

The chip is the memory controller…

Yes it’s on-die. Yes it has error reporting. Don’t spread fud. There isn’t a dedicated chip because there doesn’t need to be.

Broadcom BCM2712

In that case I incorrectly thought (like the other forum posters) it was like DDR5 on-die ECC. What you describe is better than DD5 on-die ECC. Is this error reporting supported by Linux? Is there some way I can do fault injection (e.g. undervolting the RAM) to check it's working?