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hikarudo 15 hours ago

Why 25%, shouldn't it be 12.5%? 8 ECC bits for every 64 bits.

ciupicri 13 hours ago | parent [-]

DDR5 ECC RDIMMs (R=registered) have 16 extra bits. From the specifications for Kingston's KSM64R52BS8-16MD [1]:

> x80 ECC (x40, 2 independent I/O sub channels)

On the other hand ECC UDIMMs (U=unbuffered) have only 8. From the specifications for Kingston's KSM56E46BS8KM-16HA [2]:

> x72 ECC (x36, 2 independent I/O sub channels)

Though if I remember correctly, the specifications for the older DDR4 ECC RDIMMs mention only 72 bits.

[1]: https://www.kingston.com/datasheets/KSM64R52BS8-16HA.pdf

[2]: https://www.kingston.com/datasheets/KSM56E46BS8KM-16HA.pdf